The complete guide to area defense in combat operations (tactical and offense series).
The Area Defense
An area defense capitalizes on the strength inherent in a closely integrated defensive organization on the ground. The conduct of an area defense facilitates the consolidation and reconstitution of forces in order to transition to a focus on another element of decisive action, such as stability. The commander may assign subordinate units the task of conducting an area defense as part of their mission. Subordinate echelons defend within their assigned areas of operations (AOs) as part of the larger-echelon’s operation.
GENERAL CONSIDERATIONS FOR AN AREA DEFENSE
7-1. A commander conducts an area defense when the following conditions occur:
- When directed to defend or retain specified terrain.
- When the commander cannot resource a striking force.
- The forces available have less mobility than the enemy.
- The terrain affords natural lines of resistance and limits the enemy to a few well-defined avenues of approach, thereby restricting the enemy’s maneuver.
- There is enough time to organize the position.
- Terrain constraints and lack of friendly air superiority limit the striking force’s options in a mobile defense to a few probable employment options.
- Conditions require the preservation of forces when transitioning from a focus on the conduct of offensive tasks to stability tasks and when offensive actions are superfluous to the mission.
7-2. The commander conducting an area defense combines static and mobile actions to accomplish the mission. Static actions usually consist of fires from prepared positions. Mobile actions include using the fires provided by units in prepared positions as a base for counterattacks and repositioning units between defensive positions or forward operating bases when the operation is focused on the conduct of stability tasks. The commander can use the reserve and uncommitted forces to conduct counterattacks and spoiling attacks to desynchronize the enemy forces or prevent them from massing.
7-3. The commander organizes the defending force to accomplish intelligence, security, main battle area (MBA), reserve, and sustainment missions. The commander has the option of defending forward or defending in depth. When the commander defends forward within an AO, the force is organized so that most of the available combat power is committed early in the defensive effort. To accomplish this, the commander may deploy forces forward or plan counterattacks well forward in the MBA or even beyond the MBA. If the commander has the option of conducting a defense in depth, security forces and forward MBA elements are used to identify, define, and control the depth of the enemy’s main effort while holding off secondary thrusts. This allows the commander to conserve combat power, strengthen the reserve, and better resource the counterattack.
RECONNAISSANCE AND SURVEILLANCE
7-4. The commander directs reconnaissance and surveillance assets to determine the locations, strengths, and probable intentions of the attacking enemy force before and throughout the defense. The commander places a high priority on early identification of the enemy’s main effort. The commander may need to
complement surveillance with combat actions that test enemy intentions. Fighting for information can have two benefits—it can force the enemy to reveal intentions and disrupt enemy preparations.
7-5. In the defense, reconnaissance and surveillance operations overlap the unit’s planning and preparing phases. Leaders performing reconnaissance and surveillance tasks must understand that they often deploy before the commander fully develops the plan. These leaders must be responsive to changes in orientation and mission. The commander ensures that the staff fully plans, prepares, and assesses the execution of the intelligence portion of the overall plan.
7-6. The commander balances the need to create a strong security force to shape the battle with the resulting diversion of combat power from the main body’s decisive operation. The commander usually allocates security forces to provide early warning and protect those forces, systems, and locations necessary to conduct the decisive operation from unexpected enemy contact. On a battlefield where forces are contiguous with one another, the location of security forces is usually in front of the main defensive positions. On a noncontiguous battlefield they are located on avenues of approach between the protected force and known or suspected enemy locations.
7-7. Maneuver battalion and brigade combat team (BCT) security forces normally conduct screen or guard missions. At division level and above, the commander may use a covering force. A division commander may elect to have the security force conduct a guard mission, if a corps covering force exists. Because an area security mission usually ties in closely with flank units, flank security forces are needed if there are gaps on the unit’s flanks, which occurs during noncontiguous operations, or if gaps develop during the operation. A flank screen or guard is critical if an enemy avenue of approach into the defended area from the flanks could be uncovered during the defense. A commander does not normally assign a force the mission of conducting rear guard or rear cover during contiguous operations, since it is unlikely that the force’s support area will become uncovered during the defense. The commander resources echelon support area security forces, to include a tactical combat force (TCF) or accepts the risk to the sustainment effort of not performing this function.
MAIN BATTLE AREA
7-8. The commander builds the decisive operation around identified decisive points, such as key terrain or high-payoff targets. The commander’s decisive operation in an area defense focuses on retaining terrain by using fires from mutually supporting, prepared positions supplemented by one or more counterattacks and the repositioning of forces from one location to another. The commander’s decisive operation normally involves close combat since an area defense emphasizes terrain retention.
7-9. The commander normally positions the echelon’s main body—the bulk of combat power—within the MBA where the commander wants to conduct the decisive operation. The commander organizes the main body to halt, defeat, and ultimately destroy attacking enemy forces. The majority of the main body deploys into prepared defensive positions within the MBA. However, mobile elements of the force are ready to deploy where and when needed.
7-10. The commander’s defensive plan should be able to succeed without using the reserve. However, the most likely mission of the reserve is to conduct a counterattack in accordance with previously prepared plans. Lower-echelon commanders use their reserves primarily to conduct local counterattacks to restore the integrity of their defense or to exploit opportunities. A senior commander uses the reserve to seize the initiative from the enemy when the opportunity presents itself. For example, a corps commander may target the effects of the corps reserve against enemy fire support and follow-on forces to produce that effect.
7-11. The reserve is not a committed force. The commander can assign it a wide variety of tasks on its commitment, and it must be prepared to perform other missions. In certain situations, it may become necessary to commit the reserve to restore the integrity of the defense by blocking an enemy penetration or reinforcing fires into an engagement area (EA). These secondary tasks include—
- Reinforcing the defense of committed forces.
- Blocking or containing enemy forces that penetrate friendly defensive positions.
- Relieving depleted units and providing for continuous operations.
- Reacting to threats directed against the friendly force’s sustainment effort. (This includes acting as the echelon TCF when a separate TCF cannot be resourced.)
- Extending the flanks of a defending unit to prevent its envelopment.
- Covering a retrograde movement.
7-12. Defending commanders usually have difficulties establishing and resourcing reserve forces because they are normally facing an enemy with superior combat power. Nevertheless, commanders at each echelon down to the battalion retain reserves as a means of ensuring mission accomplishment and for exploiting opportunities through offensive action. (Maneuver company commanders may retain a reserve based on the mission variables.) Commanders do not place artillery and other fire support systems in reserve. (Such systems committed to echelon support operations are not in reserve.) Each echelon’s reserve must have the mobility and striking power required to quickly isolate and defeat breakthroughs and flanking attempts. It must be able to seize and exploit fleeting opportunities in a powerful manner to throw the enemy’s overall offensive off balance. The commander must resource the reserve, so it can repeatedly attack, regroup, move, and attack again.
7-13. The size of the reserve is relative to the commander’s uncertainty about the enemy’s capabilities and intentions. The more uncertainty that exists, the larger the reserve. The reverse is also true. If the commander knows the enemy’s size, dispositions, capabilities, and intentions, only a comparatively small reserve is required.
7-14. In some situations, the commander may not be able to resource a separate reserve. Therefore, the commander may constitute all or a portion of the reserve from the security force, after it conducts a rearward passage of lines through MBA units. If the security force is the reserve for an area defense, the commander must withdraw it, so it has sufficient time to occupy its reserve position, perform the necessary degree of reconstitution, and prepare plans for its reserve role. However, this is not the preferred option. Before battle handover, the senior commander must state the acceptable risk to the security force or the disengagement criteria in quantifiable terms, such as friendly strength levels, time, or event. In this case, after completing the rearward passage, the security force moves to an assembly area to prepare for its subsequent operations. This area should be free from enemy interference and clear of MBA units, main supply routes (MSRs), and the movements of other portions of the reserve.
7-15. Once committed, the reserve’s operations usually become the echelon’s decisive operation. However, the commander can commit the reserve to shaping operations to allow the ongoing decisive operation to achieve success. It no longer constitutes the force reserve on its commitment in either case, so the commander should designate another uncommitted force as the reserve. If the commander does not have that flexibility, the commander holds the reserve for commitment at a decisive moment and accepts the associated risk.
7-16. The sustainment mission in an area defense requires a careful balance between establishing forward supply stocks of petroleum, oil, and lubricants (POL); barrier material; and ammunition in adequate amounts to support defending units and not having so many supplies located in forward locations that they cannot be rapidly moved in conformance with enemy advances. Any suitable POL, barrier material, construction equipment, and laborers that can be lawfully obtained from the civil infrastructure reduce the defending unit’s transportation requirements. Proper forecasting of supply and support requirements is important to the success of the area defense. (Commanders and staffs carefully determine the quantities of supplies to be obtained locally to avoid introducing unnecessary instability in the local economy.) Likewise, maintenance and medical support, with their associated repair parts and medical supplies, must also be forward deployed. Those systems and Soldiers that cannot be quickly returned to the battle should be rapidly evacuated from forward defensive positions to avoid unduly burdening maintenance and medical elements. (See paragraphs 6-83 through 6-91 for additional defensive sustainment considerations.)
7-17. The commander organizes an area defense by designating the MBA and assigning AOs, battle positions (BPs), or forward operating bases (FOBs) to subordinate units located within the MBA. The commander creates a security area in front of the MBA or around a base of operations. When possible, the boundaries of the subordinate elements of the security force coincide with those of the major defending units in the MBA. The security area should be deep enough to make the enemy displace as much of the enemy’s supporting forces as possible, such as cannon artillery, sensors, and air defense artillery gun systems, before carrying the attack into the MBA. The commander also designates an echelon support area. (See FM 3-90-2 for a discussion of security operations.)
7-18. Area defense maneuver graphic control measures may include EAs, the forward edge of the battle area (FEBA), the battle handover line (BHL), strong points, target reference points (TRPs), named areas of interest (NAIs), targeted areas of interest (TAIs), decision points, and various other fire control and countermobility control measures. Tactical mission tasks assigned as part of the mission can also be control measures. (Figure 7-1 depicts the most common control measures. Appendix A defines these defensive control measures.)
7-19. If the commander assigns a battle position (BP) and an AO to a subordinate, the commander gives the subordinate commander specific guidance on the initial positioning of forces. The commander ensures the synchronization of subordinate units’ defensive plans, and that control measures, such as contact points and phase lines, are sufficient to ensure the continued control of subordinates. The commander is responsible for fire and movement planning between the positions of subordinate units. If subordinate unit commanders prepare their defensive plans in isolation, one or more assailable flanks between subordinate units could easily develop. (The tactics associated with conducting a passage of lines are addressed in FM 3-90-2.)
7-20. The key to a successful area defense is the integration and synchronization of all available assets. The commander achieves this when the combined arms team is at the decisive time and place. (The general defensive planning considerations addressed in chapter 6 apply to the area defense.) The commander assigns missions, allocates forces, and apportions functional and multifunctional support and sustainment resources within the construct of decisive, shaping, and sustaining operations. The commander decides where to concentrate the effort and where to take risks. The commander can rapidly redirect attack aviation and artillery systems initially allocated to shaping operations to support decisive operations at the appropriate time. Commanders organize forces differently for contiguous and noncontiguous areas of operations. A contiguous area of operations is where all subordinate forces’ areas of operations share one or more common boundaries. A noncontiguous area of operations is where one or more of the commander’s subordinate force’s areas of operation do not share a common boundary. (See figures 7-2 and 7-3 for graphical depictions of the organization of forces for an area defense in a contiguous AO and in a noncontiguous AO.)
7-21. The commander describes the concept of operations in sufficient detail so that the staff and subordinate commanders understand precisely how the commander intends to fight the battle. The commander ensures the coordination of maneuver and supporting actions among subordinates. (ADRP 5-0 discusses the military decisionmaking process.)
7-22. The commander’s keys to a successful area defense are—
- Capability to concentrate effects.
- Depth of the defensive area.
- Ability to take full advantage of the terrain, such as intervisibility lines.
- Flexibility of defensive actions.
- Timely resumption of offensive actions.
7-23. The crux of the commander’s defensive challenge is to gain time to ensure a synchronized, effective defense. The commander organizes the defensive effort based on an analysis of the mission variables and the higher commander’s concept. When conducting an area defense while transitioning to a focus on the conduct of stability tasks, the commander may also transition to the joint operational variables—political, military, economic, social, information, and infrastructure to which the Army adds physical environment and time (PMESII-PT). (ADRP 3-0 discusses
Figure 7-3. Organization of forces for an area defense-noncontiguous area of operations
PMESII-PT in more detail.) The commander decides where to concentrate efforts and how to economize forces. The commander forces the enemy units to enter established EAs. To succeed in its area defense mission, the unit must also counteract the enemy’s initiative. The commander should take advantage of available offensive opportunities that do not risk the integrity of the defense, such as a spoiling attack or counterattack.
7-24. In planning an area defense, the commander may choose between two forms of defensive maneuver. The defending unit can organize either a defense in depth or a forward defense. A higher commander may dictate the form of maneuver or impose restrictions that eliminate a subordinate commander’s form of maneuver. These restrictions can include time, security concerns, and retention of specific terrain. These two deployment choices are not totally exclusionary. Part of a defending commander’s unit can conduct a forward defense, while the other part conducts a defense in depth.
7-25. In determining the form of maneuver, the commander decides where the defensible terrain is located within the assigned AO based on its terrain characteristics and that individual’s estimate of the enemy’s chosen course of action (COA). Those terrain characteristics include terrain relief patterns, avenues of approach into and within the AO, the location of any key or decisive terrain, and existing obstacles and choke points, to include rivers and fording sites. The other mission variables of mission, enemy, terrain and weather, troops and support available, time available, and civil considerations (METT-TC) also influence the commander’s decision.
7-26. A statement anecdotally attributed to Frederick the Great and Robert E. Lee, among others, is that the commander who attempts to defend everything, defends nothing. Therefore, the commander carefully designs the defense plan to ensure the defending force can halt the enemy attack and develop an opportunity to seize the initiative and undertake offensive actions. The cohesion of the defending force has a significant impact on the overall effectiveness of the defense. The commander must be prepared to adjust the defensive dispositions to meet changes in the enemy’s dispositions to maintain that cohesion, if the defense is to remain viable.
7-27. The area defense concept requires that units in defensive positions accomplish their mission independently or in combination by defeating the enemy by fire, absorbing the strength of the attack within the position, or destroying the enemy with a local counterattack. The commander combines the advantages of fighting from prepared positions, obstacles, planned fires, and local counterattacks to isolate and overwhelm selected enemy formations. The commander must be prepared to rapidly shift the nature and location of the main effort throughout the AO. The commander may have to reposition defending units within their defensive positions or reposition between terrain features to mass overwhelming fires against the attacking enemy. The commander’s defensive plan designates axes of advance and routes for the commitment or movement of reserves, or the forward or rearward passage of one unit through another. It should identify air axes for aerial maneuver by attack helicopters, air assault units, or fixed-wing aircraft. The operations process identifies decision points associated with the initiation of these counterattacks, repositioning of forces, and other actions. This capability to dynamically reposition is dependent on the defending force having superior tactical mobility. Without tactical mobility, defending forces stay in their prepared positions and accept the possibility of becoming decisively engaged.
7-28. The commander assigning the defensive mission defines the area to defend. A commander defending on a broad front is forced to accept gaps and conduct noncontiguous operations. The forward line of own troops (FLOT) will not be contiguous. Defending shallow areas of operations reduces flexibility and requires the commander to fight well forward. Narrow frontages and deep areas of operations increase the elasticity of an area defense by increasing the commander’s maneuver options.
7-29. The ideal area defense is one where effective mutual support exists throughout the width and depth of the defender’s tactical positions. The commander organizes and occupies these positions based on their natural defensive strength; their retention ensures the integrity of the defense whether the defending commander employs a defense in an AO, defends by BP, or employs a combination of both. The defending unit maintains tactical integrity within each defensive area. A unit conducting an area defense normally addresses the security requirements of each flank by assigning responsibility to a subordinate element or organizing a security force to specifically accomplish that mission.
DEFENSE IN DEPTH
7-30. A defense in depth is normally the commander’s preferred option. Forces defending in depth absorb the momentum of the enemy’s attack by forcing the enemy to attack repeatedly through mutually
supporting positions in depth. Construction of these positions requires significant engineer and other resources dedicated to survivability and countermobility. Depth gives the commander’s fire support assets time to deliver devastating effects and affords the defending commander multiple opportunities to concentrate the effects of overwhelming combat power against the attacking enemy. Depth also provides more reaction time for the defending force to appropriately respond to the attack. The commander continues to gather additional information about the attacking enemy’s intentions and capabilities between the time combat starts and the time the enemy commits to a COA. This reduces the risk of the enemy force quickly penetrating the main line of defense along an unexpected direction.
7-31. The commander also employs a defense in depth when the enemy has the capability to employ large quantities of precision-guided munitions or weapons of mass destruction. A defense in depth results in friendly units and facilities being dispersed throughout the defensive AO. The commander takes area damage-control measures to reduce the effects of weapons of mass destruction on the friendly force and denies the enemy lucrative targets. The degree of dispersal adopted by defending forces is both a function of the enemy’s capabilities and the friendly forces’ capability to rapidly concentrate overwhelming combat power at decisive points.
7-32. The commander positions defending units in successive layers of battle positions along likely enemy avenues of approach when conducting a defense in depth. (See figure 7-4.) The commander usually decides to conduct a defense in depth when—
- The mission is not restrictive and allows the commander to fight throughout the depth of the battlefield.
- The terrain does not favor a defense well forward, and there is better defensible terrain deeper within the AO.
- The AO is deep compared to its width, and there is significant depth available.
- The cover and concealment on or near the FEBA is limited.
- The enemy has several times the combat power of the defender.
7-33. Large units, such as a division or corps, employing a defense in depth can conduct an area defense on a wider frontage than they can if they adopt a forward defense because a forward defense has no time or space to reposition forces. A defense in depth allows the commander to use security and forces in the forward part of the MBA to identify the enemy’s decisive operation and control the depth of the enemy’s penetration into the MBA. By their defensive actions, these forces provide the commander with time to react to enemy actions and allow the defending commander to take offensive steps that eliminate enemy options, such as conducting a counterattack into the flank of an enemy force.
7-34. The commander conducts the decisive operation from forward defensive positions near the FEBA in a forward defense. (See figure 7-5 on page 7-8.) The commander concentrates a significant portion of available combat power into EAs along the FEBA. The intent is to prevent significant enemy penetration into the defensive area. The commander conducting a forward defense fights to retain these positions along the FEBA and violently counterattacks any enemy penetration. However, if the enemy penetrates the main defensive positions, the defender’s lack of depth may allow the enemy to rapidly exploit success.
7-35. In general, the commander uses a forward defense when a higher commander directs the commander to retain forward terrain for political, military, economic, and other reasons. Alternatively, a commander may choose to conduct a forward defense when the terrain in that part of the AO—including natural obstacles—favors the defending force because—
- The best defensive positions are located along the FEBA.
- Strong natural obstacles are located near the FEBA.
- Natural EAs occur near the FEBA.
- Cover and concealment in the rear portin of the AO are limited.
POSITIONING THE RESERVE
7-36. Whatever the commander’s choice—forward or in depth—once the enemy commits forces, the defending commander has the ability to seize the initiative by counterattacking over familiar ground to destroy a halted, disorganized enemy, while the counterattacking force is protected by overwatching fires from friendly positions. Whenever possible, the commander should direct these counterattacks against the enemy’s rear or flanks. The commander’s reserve is a key component of the counterattack.
7-37. When deciding where to place the reserve, the commander decides whether to orient the reserve on its most likely mission or its most important mission. The commander and staff expend significant effort during the planning process to ensure the commander can effectively use the reserve when needed. The commander may locate the reserve within the AO where it can employ the road network to rapidly displace throughout the AO in response to a number of opportunities or contingencies. The commander must consider terrain, MSRs of forward units, enemy avenues of approach, and probable enemy penetrations when determining the exact location for the reserve. The commander may choose to initially position the reserve in a forward location to deceive the enemy and obscure subordinate unit boundaries, especially those of dissimilar units such as armor and light infantry.
7-38. In restrictive terrain that lacks routes for movement, the commander can task organize the reserve into small elements and position them where they can react quickly to local combat developments. This dispersion provides increased protection but reduces the ability of the reserve to mass fires. Covered lateral and forward high-speed deployment routes should be available. The reserve must have movement priority along those routes. The commander must ensure the maintenance of communication between these dispersed elements. This may require establishing retransmission nodes for combat net radios. In open terrain, the commander maintains a centrally located reserve positioned somewhat farther from the FLOT. The commander considers the enemy’s potential to employ weapons of mass destruction and conduct air interdiction when deciding where to position the reserve.
7-39. Whenever possible, the commander positions the reserve beyond the enemy’s direct fire range. This is easier to achieve at higher echelons than at lower echelons. The reserve takes defensive measures to prevent being acquired and attacked by enemy indirect fire systems. These include camouflage, local security, and control of electronic emissions.
7-40. The commander also plans how to reconstitute a reserve on commitment of the original reserve. The commander most easily designates subordinate unit reserves as the new echelon reserve. If the higher headquarters has not committed its reserve, the commander has more flexibility and can take greater risk in employing the reserve.
SPOILING ATTACKS AND COUNTERATTACKS
7-41. A spoiling attack preempts or seriously impairs the enemy’s ability to launch an attack, while a counterattack prevents the enemy from exploiting successes. The forces conducting either form of attack must be large and strong enough to develop the situation, defend themselves against those enemy forces that they expect to encounter, and force the enemy to react, placing the enemy’s attack plan at risk.
7-42. The commander considers the enemy situation and estimates the time and distance factors of any follow-on enemy forces in planning either a spoiling attack or a counterattack by the reserve and other forces. Then the commander determines which units will attack, where they will be after the attack, and what interdiction is necessary to isolate the targeted enemy element. (See figure 7-6.) Counterattacking forces plan to avoid enemy strength when possible. The most effective attacks seize strong positions that permit the counterattacking force to deliver fire on an exposed enemy unit’s flanks and rear. If it is tasked to stay and defend against enemy follow-on forces, the counterattacking force must establish a viable defensive position before any following enemy units can make contact.
7-43. Counterattack plans include assumptions regarding the size and shape of the anticipated penetration or enemy formation, the strength and composition of the enemy force, and the status of the reserve and forces in the MBA. Other factors that affect the counterattack include the capability to contain the enemy, shaping operations to support the attack, and the strength and responsiveness of the reserve at the time of the counterattack.
7-44. The commander’s staff prepares counterattack plans and then allocates subordinate headquarters sufficient time to make their plans. The control measures for a counterattack are the same ones discussed in chapter 3 for the attack. If possible, the commander distributes counterattack plans along with the base defense plan. Reserve unit commanders conduct detailed counterattack planning that includes conducting reconnaissance, selecting multiple routes, determining time and space factors, rehearsing, coordinating with appropriate elements of the forward defending force, and fire planning. The commander adjusts counterattack plans as necessary based on the lessons learned during rehearsals.
7-45. Enemy movement into an NAI helps the commander determine the enemy’s scheme of maneuver and possible objectives. The commander uses decision points and NAIs throughout the AO to trigger the counterattack. The commander identifies TAIs for attack to support area defensive actions.
CIVIL CONSIDERATIONS IN THE AREA DEFENSE
7-46. The unit’s defensive plans must address how the preparations for, and the conduct of, the area defense impact the civilian population of the AO. This includes the conduct of noncombatant evacuation operations for U.S. civilians and other authorized groups. The commander’s legal obligations to that civilian population must be met. Ideally, the host nation government will have the capability to conduct the five primary stability tasks. To the extent that a host nation government is unable to conduct the immediate subordinate stability tasks, the defending unit will have to attempt to make up the shortfall.
7-47. Commanders planning an area defense focus their preparations on planning those additional reconnaissance and surveillance operations required to answer the commander’s critical information requirements, refining the plan, increasing coordination and synchronization, and conducting shaping actions within the force’s capability and operations security guidelines. If the commander decides that a deliberate defense must be conducted but knows that the enemy will attack before the defending force is prepared, the commander may have to commit substantial forces to security operations or conduct a spoiling attack. This buys time and space to prepare for a deliberate defense.
7-48. A unit normally transitions to the defense after it completes the deployment process of force projection, completes its offensive actions, or is in an assembly area. The commander issues a warning order stating the mission and identifying any special considerations. The unit staff conducts detailed planning while the rest of the unit completes its current mission. The staff coordinates for the pre-positioning of ammunition and barrier material in a secure area near the unit’s defensive positions before starting the operation.
7-49. Before occupying any position, leaders at all echelons conduct some type of reconnaissance. This reconnaissance effort is as detailed as the mission variables of METT-TC permit. It may consist of a simple map reconnaissance or a more detailed leaders’ reconnaissance that determines the initial layout of the new position. Leaders also take advantage of digital enablers, such as the Distributed Common Ground System and geospatial intelligence (GEOINT), to increase their understanding of their area of operations.
7-50. The defending unit occupies its defensive positions as soon as practical after receiving the mission. It conducts reconnaissance of the defensive area and establishes a forward security area before occupying defensive positions. The unit may pre-position supplies such as ammunition and barrier materiel once it establishes security. The unit can accomplish many defensive tasks simultaneously; the mission variables of METT-TC are the deciding consideration in establishing priorities of work. Those priorities may be—
- Establishing local security and deploying a security force.
- Identifying EAs where the commander wants to engage and destroy the enemy.
- Planning fire control measures, such as TRPs, trigger lines, and final protective fires to support the EAs.
- Positioning key weapon systems to engage into the EAs and TRPs and develop range cards and sector sketches.
- Positioning observers who can see both targets and trigger lines.
- Positioning obstacle groups to support weapon systems.
- Designating and clearing fields of fire.
- Preparing primary fighting positions based on the anticipated fighting conditions, such as the time of day and weather conditions.
- Emplacing obstacles and surveying indirect fire targets to support these obstacles.
Providing concealment and camouflage for fighting and survivability positions as they are constructed.
- Positioning any available critical friendly zones over friendly positions by establishing sensor coverage and quickfire links between the sensor and shooter.
- Installing night and limited-visibility aids, such as thermal hot spots and chemical lights on TRPs during daylight.
- Updating range cards and sector sketches as required.
- Preparing alternate fighting positions.
- Designating and preparing supplementary positions.
- Designating hide positions and rehearsing movements to and from fighting positions. (Units may place their combat and tactical vehicles in hide positions at any time while preparing the defensive position.)
- Positioning the reserve.
- Establishing contact points with any adjacent units so that the defensive efforts of both units can be tied together.
- Emplacing communications assets in order to support the unit’s primary, alternate, contingency, and emergency communications for each primary, supplemental, and alternative position.
- Improving mobility on counterattack routes.
- Prestocking ammunition in revetments or bunkers where it can survive the enemy’s preparatory fires.
- Rehearsing movements under daylight and limited-visibility conditions.
- Establishing sleep and rest plans.
- Continuing to improve the defense.
7-51. Survivability positions enhance the strength of a defensive position by providing Soldiers and weapon systems with some degree of cover from enemy fires. Units initiate construction of survivability positions in accordance with their priority of work and continue to build and improve them until the last possible moment. The degree of overhead cover provided varies with the location of the sheltered troops and enemy capabilities. As time and resources allow, the defending unit improves communication routes throughout its defensive positions to ease movement of supplies and forces, particularly the reserve. It quickly establishes tactical communications among its various subordinate elements to reduce its electromagnetic signature.
7-52. The defending unit rehearses how to move from its hide positions to its primary positions and how it will occupy alternate and supplementary positions to continue to engage the enemy, if the enemy’s attack progresses into the unit’s defensive positions. These rehearsals establish the time necessary to conduct these movements under different environmental conditions. It modifies existing plans based on the results of rehearsals and changes in the mission variables of METT-TC. The commander takes steps to ensure that the routes taken during these rehearsals do not show obvious signs of heavy use. These steps can include the conduct of only dismounted rehearsals, only moving one vehicle per platoon, and taking steps to eliminate signs of movement such as sweeping snow back over the tracks made during the rehearsal.
7-53. The commander ensures close coordination among subordinates. During the preparation phase, subordinate commanders are taken to a vantage point in the MBA to rehearse the battle and plan coordination among their units if such a site is available. This helps in transmitting the commander’s intent and in establishing common control measures for subordinate units.
7-54. The location, composition, and movement of the reserve are essential elements of friendly information. Enemy reconnaissance efforts focus on finding the reserve and reporting when and where it is committed. Avoiding detection by the enemy is vital to the success of the reserve.
7-55. The commander integrates the sustainment rehearsal into the maneuver rehearsal to verify that routes for support do not cross or conflict with routes used by reserve forces or other maneuver elements. The commander should balance the use of ammunition caches against the defending unit’s ability to guard them. The commander should also ensure that alternate MSRs are adequate to accommodate contingency plans and that changing MSRs can be accomplished effectively.
7-56. The commander ensures that available combat multipliers are completely integrated with the unit’s intended maneuver. This includes the use of camouflage, military deception, and smoke to confuse enemy reconnaissance assets. After issuing the order and receiving backbriefs from subordinate commanders and other leaders, the commander verifies that they have a common understanding of the plan and can execute it with minimal guidance.
7-57. A defending unit within the MBA uses a variety of tactics, techniques, and procedures to accomplish the mission. At one end of the defensive continuum is a totally static defense oriented on terrain retention. This defense depends on the use of firepower from fixed positions to deny the enemy terrain. At the other end is a dynamic defense focused on the enemy. That defense depends on maneuver to disrupt and destroy the enemy force.
7-58. A commander combines the static element to control, stop, or canalize the attacking enemy force and the dynamic element to strike and defeat that force. A successful area defense uses forces in relatively fixed positions to create the opportunity for the reserve to strike at the enemy from an unanticipated direction and strength. (See figure 7-7.) The defending force repeatedly lures the enemy into EAs where it kills selected portions of the enemy force.
7-59. In an area defense, defending forces fight mainly from prepared, protected positions to concentrate combat power against attempted enemy breakthroughs and flanking movements. The commander uses mobile forces to cover gaps between defensive positions, reinforce those positions as necessary, and counterattack to seal penetrations or block enemy attempts at flanking movements.
7-60. Conducting shaping operations in an area defense is similar to shaping operations in the offense. The mission variables of METT-TC determine how closely the commander synchronizes shaping operations with the decisive operation. The commander conducts shaping operations designed to regain the initiative by limiting the attacker’s options and disrupting the enemy’s plan. Shaping operations prevent enemy forces from massing and create windows of opportunity for the conduct of a decisive offensive task, allowing the defending force to defeat the attacking enemy in detail. The commander also employs shaping operations to disrupt enemy operations by attacking command posts at critical stages in the battle or by striking and eliminating key elements, such as river crossing equipment and supplies in a region that contains numerous unfordable rivers. Reconnaissance and security operations are normally components of the echelon’s shaping operations.
7-61. As in the offensive articles of this series, this article divides execution into five steps for discussion purposes. These steps are:
- Gain and maintain enemy contact.
- Disrupt the enemy.
- Fix the enemy.
- Follow through (counterattack).
7-62. This does not mean that these steps occur sequentially; they may occur simultaneously. The first three of these steps are almost always shaping operations. Depending on the circumstances, either of the last two steps may be the echelon’s decisive operation.
GAIN AND MAINTAIN ENEMY CONTACT
7-63. Gaining and maintaining enemy contact in the face of the enemy’s determined efforts to destroy friendly reconnaissance and surveillance assets is vital to the success of defensive actions. As the enemy’s attack begins, the defending unit’s first concerns are to identify committed enemy units’ positions and capabilities, determine the enemy’s intent and direction of attack, and gain time to react. Initially, the commander accomplishes these goals in the security area. The sources of this type of intelligence include reconnaissance and security forces, intelligence units, special operations forces, and aviation elements. Battalions and companies are increasingly able to access combat information provided by technical means belonging to higher echelons, such as unmanned aircraft systems and signals intelligence, to provide the required reaction time. The commander ensures the distribution of a common operational picture throughout the force during the battle as a basis for subordinate commanders’ actions. The commander uses the information available, in conjunction with military judgment, to determine the point at which the enemy commits to a COA.
7-64. The security force seeks to strip enemy reconnaissance forces and hide the defending force’s dispositions, capabilities, and intent at the same time as friendly reconnaissance and surveillance assets help to determine the enemy’s chosen COA. Ideally, the engagement in the security area should force the enemy to conduct a movement to contact against a prepared defense.
7-65. A single force in the security area can perform both reconnaissance and security functions. The security force uses every opportunity for limited offensive action to delay and harass the enemy and to gain information. As the security element displaces, the commander makes preparations to pass it through or around the MBA force as quickly as possible by using multiple passage points, gaps, or lanes along the FEBA. This usually occurs in one location at a time until the security force has completely withdrawn. However, the security force may pass in sequence based on enemy pressure. Transfer of responsibility occurs forward of the FEBA at the BHL. (See figure 7-8 on page 7-14.) Taking advantage of previous liaison and plans, the security force makes any required last-minute coordination with MBA forces at contact points to ensure its rapid passage through the MBA force.
7-66. The entire security force should not withdraw automatically as soon as the first enemy units reach the FEBA. The commander can leave in place security elements located in areas where the enemy has not advanced. The security force adjusts to the enemy’s advance and continues to conduct security operations as far forward as possible. It continues to resist the enemy’s shaping operations, such as the enemy’s reconnaissance effort, thereby upsetting the enemy’s coordination and allowing the MBA commander to fight one engagement or battle at a time. Doing this increases the chances for success even if the enemy attack penetrates the MBA in one or more areas. In some cases, the security force can attack the enemy force from its rear, engage high-payoff targets, or drive between echelons to isolate leading enemy units.
7-67. As the enemy force approaches the MBA, the commander may order reconnaissance and surveillance assets within the security force to displace to one or both sides of the enemy penetration and continue to maintain surveillance. By observing and providing access to enemy flanks, reconnaissance and surveillance elements can facilitate the conduct of friendly counterattacks. However, to prevent the encirclement of these assets, the commander may plan to monitor those areas where the enemy has not advanced into the MBA solely by technical means.
7-68. Commanders coordinate the battle handover between the security force and MBA forces as quickly and efficiently as possible to minimize their vulnerability to enemy fire. The security force commander must retain freedom to maneuver until the initiation of the passage of lines. The commander’s fire support assets help cover the withdrawal of security forces. Functional and multifunctional support and sustainment elements of the security force leave the security area as early as possible to avoid hampering the movement of maneuver forces. Normally, battalion-sized units of the security force hand off the battle to the brigade combat teams through which they pass. (See FM 3-90-2 for a discussion of the tactics associated with the conduct of a rearward passage of lines.)
7-69. The commander must consider the security force’s next mission before battle handover between the security force and the MBA force. Factors that may affect this decision are the status of the security force, its subsequent mission preparation requirements, and the size and nature of the reserve required by the situation. The commander may decide to employ it immediately as the reserve, which would release the initial reserve for other tasks. Alternately, the commander may decide to use the security force to conduct additional security operations on the flanks of MBA forces as the battle progresses. However, it may be some time before the security force is ready for commitment. Therefore, the commander is more likely to wait until the security force has been reconstituted and the initial reserve committed before designating the former security force as the reserve.
7-70. The commander should base the location of the security force’s assembly area on its follow-on mission. The commander locates those assembly areas to rapidly support ongoing operations yet keep withdrawn security units from interfering with ongoing decisive and shaping operations. After passage, the security force normally moves to these locations to prepare for subsequent operations. At a minimum, the commander must rearm and refuel the security force. Additional sustainment concerns include casualty evacuation, maintenance requirements, and resupply.
DISRUPT THE ENEMY
7-71. The commander executes shaping operations, to include the conduct of military deception operations, to disrupt the enemy regardless of the enemy’s location within the AO. After making contact with the enemy, the commander seeks to disrupt the enemy’s plan, the enemy’s ability to control forces, and the enemy’s combined arms team. Ideally, the results of the commander’s shaping operations should force a disorganized enemy, whose ability to synchronize its elements has been degraded, to conduct a movement to contact against prepared defenses. Once the process of disrupting the attacking enemy begins, it continues throughout the conduct of the defense.
7-72. The commander initiates shaping operations simultaneously with the preparation of MBA positions. These shaping operations typically focus on enemy high-payoff targets, such as command and control nodes, engineer, fire support, and air defense assets for destruction or disruption. They can also force the enemy to use avenues of approach covered by friendly EAs. These shaping operations destroy the enemy’s cohesion and disrupt the tempo of the enemy’s approach to the MBA. This, in turn, disrupts the timely introduction of enemy follow-on forces into the engagement. For example, electronic warfare directed against the enemy’s command and control nodes and air defense assets increases the enemy’s vulnerability to other shaping operations while simultaneously slowing the enemy’s reaction to these shaping operations. (See FM 3-36 for a discussion of electronic warfare.) Follow-on engagements focus on degrading the enemy’s fire support and engineer assets, thereby disrupting the movement of enemy approaching units.
7-73. Other targets for shaping operations include enemy reconnaissance and intelligence assets. Destroying these assets allows the commander to repeatedly force enemy units to deploy into combat formations on ground of the commander’s choosing, thus contributing to the disruption and desynchronization of the enemy’s plan. The timing of these shaping operations is important. The enemy cannot be allowed to recover from their effects before the decisive operation. The commander may also execute offensive actions to further disrupt the enemy, such as spoiling attacks, raids, ambushes, feints, or demonstrations.
FIX THE ENEMY
7-74. The commander does everything possible to limit the options available to the enemy when conducting an area defense. In addition to disrupting the enemy, the commander conducts shaping operations to constrain the enemy into a specific COA, control enemy movements, or fix the enemy in a given location. These actions limit the enemy’s options. While executing these operations, the commander continues to find, delay, or attrit enemy follow-on and reserve forces to keep them from entering the MBA.
7-75. The commander has several options to help fix an attacking enemy force. The commander can design shaping operations—such as securing the flanks and point of a penetration—to fix the enemy and allow friendly forces to execute decisive maneuver elsewhere. Combat outposts and strong points can also deny enemy movement to or through a given location. (See chapter 6.) A properly executed military deception operation can constrain the enemy to a given COA.
7-76. The commander uses obstacles covered by fire to fix, turn, block, or disrupt to limit the enemy’s available options. Properly executed obstacles are a result of the synthesis of top-down and bottom-up obstacle planning and emplacement. Blocking forces can also affect enemy movement. A blocking force may achieve its mission from a variety of positions depending on the mission variables of METT-TC.
7-77. In an area defense, the decisive operation occurs in the MBA. This is where the effects of shaping operations, coupled with sustaining operations, combine with the decisive operations of the MBA force to defeat the enemy. The commander’s goal is to prevent the enemy’s further advance by using a combination of fires from prepared positions, obstacles, and mobile reserves.
7-78. Generating massed effects is especially critical to the commander conducting the defense of a large area against an enemy with a significant advantage in combat power. The attacker has the ability to select the point and time of the attack. Therefore, the attacking enemy can mass forces at a specific point, thus dramatically influencing the ratio of forces at the point of attack. An enemy three-to-one advantage in overall combat power can easily turn into a local six-to-one or higher ratio. The defending commander must quickly determine the intent of the enemy commander and the effects of terrain. This allows defending units and their weapon systems to concentrate the effects of combat power against the enemy at those points and restore a more favorable force ratio.
7-79. Forces in the MBA assume responsibility for the battle at the BHL. As the security force approaches the FEBA, it may be necessary to increase the intensity of fire support from the MBA to allow the security force to break contact. Both direct and indirect fire assets from MBA forces provide support to cover the withdrawal of the security force and to close passage lanes through obstacle complexes. The commander may also employ smoke to assist the security force with breaking contact with the enemy. The security force’s withdrawal through the forward positions of the MBA must be carefully planned and coordinated. The commander must guard gaps in obstacles left for the withdrawal of the security force and arrange for closing them after the passage of the security force.
7-80. After the attacking enemy force reaches the MBA, it tries to find weak points and attempts to force a passage, possibly by a series of probing attacks. As the attack develops, defending units engage the enemy’s lead forces. The enemy advance may slow because of canalization and the increased density of forces resulting from limited maneuver space, presenting good targets for defensive fire and air support. The maximum effects of simultaneous and sequential fires are brought to bear at this stage of the battle.
7-81. The commander’s subordinate elements maneuver using massed direct and indirect fire and movement to gain positional advantage over the assaulting enemy force. The commander also directs the engineer obstacle and sustainment effort by the assignment of priorities. The commander must reposition forces to meet the enemy where the enemy actually is rather than where the commander projected that the enemy would be. The commander directs operations and supports subordinate elements by providing the necessary functional and multifunctional support and sustainment assets. The commander controls the commitment of the echelon reserve and, at division echelon and above, engages enemy follow-on forces with long-range rockets and air support. If enemy follow-on forces can be delayed, the enemy’s attack may be defeated in detail, one echelon at a time. If the defending unit can force the enemy to commit follow-on forces sooner than planned, it can disrupt the enemy’s timetable, which can lead to the creation of exploitable gaps between the committed and subsequent echelons.
7-82. Gaps between defensive positions may be necessary, but the commander does not leave them where the enemy’s probable main effort will be. They are kept under surveillance, covered by fire or, where possible, blocked by barriers or repositioned friendly forces. The commander clearly defines the responsibility for dealing with each enemy penetration. The commander leverages the use of choke points and obstacles to prevent enemy penetration. If the enemy succeeds in penetrating the MBA, the commander blocks the penetration immediately and destroys this enemy force as soon as possible, using the mobile reserve. The commander may extend actions within the depth of the AO to counter enemy penetrations that cannot be stopped farther forward.
7-83. The commander does not allow the attacking enemy to consolidate, unless it fits the scheme of maneuver. The commander conducts a local counterattack with all available local resources to prevent the enemy from consolidating gains. The lowest possible echelon conducts this local counterattack; however, the commander must be aware of the problem of piecemeal commitment. A unit does not abandon a position unless it fits within the higher commander’s intent, or that higher commander grants permission to do so. If the defending force is unable to repulse the enemy, it tries to contain the enemy penetration until it can attack in concert with major counterattacking forces. The commander coordinates counterattacks with the efforts of the fire support system.
7-84. Although the commander plans for the counterattack in defensive planning, the plan may not correspond exactly with the existing situation when the counterattack is launched. As the situation develops, the commander reassesses the plan based on a revised situational understanding that results from an updated common operational picture as new intelligence and combat information becomes available to answer the following questions:
- Is a counterattack feasible, or should the commander use the reserve to contain enemy successes?
- When and where should the defending forces counterattack?
- In the case of enemy penetrations, what should the defending forces counterattack, and what should they block or contain?
- Is there enough time to complete the counterattack before the arrival of enemy follow-on forces?
- Can the counterattack be conducted using only available fires or must ground maneuver forces be committed?
7-85. When counterattacking, the commander employs all available resources necessary to ensure success. The reserve’s counterattack usually becomes the echelon’s decisive operation on its commitment, so the commander avoids its premature or piecemeal commitment. One of the commander’s most critical decisions is committing the reserve. The commander may reinforce the reserve force before its commitment to give it greater capability to counter enemy action. The commander does not counterattack as an automatic reaction to an enemy penetration, nor does the commander commit the reserve solely because the enemy has reached a certain phase line or other location. The commander may employ fire support assets and local counterattacks by forces already defending to destroy, disrupt, or attrit enemy penetrations, thus avoiding the need to commit the reserve. When possible, the commander launches the counterattack when the enemy presents a flank or rear, overextends, or the enemy’s momentum dissipates. Once the flanks of the enemy’s main effort are identified, the commander can target counterattacks to isolate and destroy enemy forces within the MBA.
7-86. Sometimes the commander may determine that the reserve is unable to conduct a successful counterattack. In this case, the commander uses available resources to block, contain, or delay the enemy to gain time to employ higher-echelon reserves. In these cases, the commander and staff must plan how to integrate reinforcing companies and battalions into the defensive scheme, adjust boundaries, and place battle positions. The commander plans the routes these units will use, and what adjustments will be necessary in existing mission command arrangements. The commander can speed the process of positioning and moving reinforcements or the reserve by designating routes, allocating mobility assets, and providing traffic-control personnel and guides at contact points to lead and brief them on the situation. Maneuver battalion scouts, military police, and reconnaissance units are typically the assets used to provide traffic control during the movement of these reserves because they have the combat power to protect themselves from small enemy forces that may be encountered in this type of situation.
FOLLOW THROUGH (COUNTERATTACK)
7-87. The purpose of defensive actions is to retain terrain and create conditions for a counteroffensive that regains the initiative. The area defense does this by causing the enemy to sustain unacceptable losses short of any decisive objectives. A successful area defense allows the commander to transition to an attack. An area defense could also result in a stalemate with both forces left in contact. Finally, it could result in the defender being overcome by the enemy attack and needing to transition to a retrograde operation. Any decision to withdraw must take into account the current situation in adjacent defensive areas. Only the commander who ordered the defense can designate a new FEBA or authorize a retrograde operation.
7-88. During this follow-through period, time is critical. Unless the commander has a large, uncommitted reserve prepared to quickly exploit or reverse the situation, the commander must reset the defense as well as maintain contact with the enemy. Time is also critical to the enemy, because the enemy will use it to reorganize, establish a security area, and fortify positions.
7-89. There is a difference between local counterattacks designed to restore the defense and a decisive operation designed to wrest the initiative from the enemy force and then defeat it. To conduct a decisive counterattack, the defending force must bring the enemy attack to or past its culminating point before it results in an unacceptable level of degradation to the defending force. To do this, the defending force must disrupt the enemy’s ability to mass, causing the enemy to disperse its combat power into small groups or attrit enemy forces to gain a favorable combat power ratio. The defending force must continue to disrupt the enemy’s ability to introduce follow-on forces and attack the defender’s sustainment system. In the defense, the commander must prepare to quickly take advantage of fleeting opportunities, seize the initiative, and assume the offense. Ideally, the commander already has a counterattack plan appropriate to the existing situation. The commander must rapidly reorganize and refit selected units, move them to attack positions, and attack. Alternatively, the commander must conduct an attack using those units already in contact with the enemy, which is normally the least favorable COA.
7-90. It is extremely difficult for the enemy to fight a defensive battle in response to a friendly counterattack after the enemy reaches a culminating point for the following reasons:
- Defensive preparations are hasty.
- Forces are not adequately organized for defense.
- Reorganizing for a defense requires more time than the friendly commander allows.
- The enemy force is dispersed, extended in depth, and weakened.
- Enemy attacks rarely culminate on ground ideally suited for defense.
- Physical fatigue.
7-91. The shift to a defense requires enemy soldiers to make a psychological adjustment. Enemy soldiers who have become accustomed to advancing, and thus winning, must now halt deep in the defending force’s territory and fight defensively, sometimes desperately, on new and often unfavorable terms. If the enemy commander decides to conduct retrograde operations to more defensible ground, enemy soldiers will tend to find it even harder to adjust psychologically. The commander conducts prior planning to develop decision points and control measures, such as retrograde routes, objectives, and target reference points to exploit the opportunities offered in this situation.
7-92. If the defensive battle leads to a stalemate with both forces left in contact, the defending force commander seeks to retain the initiative and set the conditions for the next encounter. The commander prepares the defending unit to move rapidly to a subsequent defensive position during a lull in the battle because it is risky to defend from the same position twice. The enemy will know the location of the defending force’s position and subject it to supporting fires unless the defending force moves. The defending unit should normally stay in place and continue to fight unless it can suppress the enemy’s approaching forces or take other actions to distract the enemy. This is because of the risk to a unit when it moves out of its prepared positions while still under enemy pressure.
7-93. If the defending unit is unable to maintain the integrity of its defense, it must transition to a retrograde operation or risk destruction. The commander must analyze how to execute this transition and prepare contingency plans. If the situation requires a retrograde movement, the commander conducts the operation according to the retrograde fundamentals and principles addressed in chapter 9. In the retrograde, if the defending force can trade space for time without sustaining unacceptable losses, the commander can usually reestablish the conditions required for a successful defense.