MOVEMENT AND MANEUVER

3-106. Maneuver considerations employ direct fire weapons on the battlefield. In the defense, weapons positioning is critical to the Infantry platoon's and squad’s success. Weapons positioning enables the platoon to mass fires at critical points on the battlefield and shift fires as necessary. The platoon leader exploits the strengths of his weapons systems while minimizing the platoon's exposure to enemy observation and fires.

3-107. If the platoon or squad are designated in a reserve role positioning the reserve in a location where it can react to several contingency plans is vital to success. The platoon leader considers terrain, traffic of roads, potential engagement area, probable points of enemy penetrations, and commitment time. The Infantry battalion commander can have a single reserve under battalion control, or, if the terrain dictates, the Infantry company can designate its own reserves. The reserve should be positioned in a covered and concealed position. Information concerning the reserve may be considered EEFI and protected from enemy reconnaissance. The commander might choose to position his reserve forward initially to deceive the enemy, or to move the reserve occasionally to prevent it from being targeted by enemy indirect fires.

DEPTH AND DISPERSION

3-108. Dispersing positions laterally and in-depth helps to protect the force from enemy observation and fires. The positions are established in depth, allowing sufficient maneuver space within each position to establish in depth placement of weapons systems, and Infantry elements. Engagement areas are established to provide for the massing of fires at critical points on the battlefield. Sectors of fire are established to distribute and shift fires throughout the extent of the engagement area. Once the direct fire plan is determined, fighting positions are constructed in a manner to support the fire plan.

FLANK POSITIONS

3-109. Flank positions enable a defending force to fire on an attacking force moving parallel to the defender's forces. A flank position provides the defender with a larger and more vulnerable target while leaving the attacker unsure of the defense location. Major considerations for employment of a flank position are the defender's ability to secure the flank and his ability to achieve surprise by remaining undetected. Fire control and fratricide avoidance measures are critical considerations in the employment of flank positions. (See appendix B of this publication for more information.)

DISPLACEMENT PLANNING

3-110. Disengagement and displacement allow the platoon to retain its flexibility and tactical agility in the defense. The ultimate goals of disengagement and displacement are to enable the platoon to avoid being fixed or decisively engaged by the enemy. The overarching factor in a displacement is to maintain a mobility advantage over the enemy. The platoon leader must consider several important factors in displacement planning. These factors include, among others —

• The enemy situation, for example, an enemy attack with one company-size enemy unit might prevent the platoon from disengaging.
• Disengagement criteria.
• Availability of direct fire suppression that can support disengagement by suppressing or disrupting the enemy.
• Availability of cover and concealment, indirect fires, and obscurants to assist disengagement. Obstacle integration, including situational obstacles.
• Positioning of forces on terrain that provides an advantage to the disengaging elements such as reverse slopes or natural obstacles.
• Identification of displacement routes and times when disengagement or displacement will take place. Routes and times are rehearsed.
• The size of the friendly force that must be available to engage the enemy in support of the displacing unit.

3-111. While disengagement and displacement are valuable tactical tools, they can be extremely difficult to execute in the face of a rapidly moving enemy force. In fact, displacement in contact poses such great problems that the platoon leader thoroughly plans for it and rehearses displacement before conducting the defense. He then carefully evaluates the situation when displacement in contact becomes necessary to ensure it is feasible and does not result in unacceptable personnel or equipment losses.

DISENGAGEMENT CRITERIA

3-112. Disengagement criteria dictate to subordinate elements the circumstances, in which they will displace to alternate, supplementary, or subsequent positions. The criteria are tied to an enemy action, such as an enemy unit advancing past a certain phase line. They also are linked to the friendly situation. For example, the criteria might depend on whether artillery or an overwatch element can engage the enemy. Unique disengagement criteria are developed during the planning process for each specific situation.

DIRECT FIRE SUPPRESSION

3-113. The attacking enemy force must not be allowed to bring direct and indirect fires to bear on a disengaging friendly force. Direct fires from the base-of-fire element, employed to suppress or disrupt the enemy, are the most effective way to facilitate disengagement. The platoon may receive base of direct fire support from another element in the company, but in most cases, the platoon establishes its own base-of-fire element. Having an internal base of fire requires the platoon leader to sequence the displacement of his forces.

COVER AND CONCEALMENT

3-114. The platoon and subordinate squads use covered and concealed routes when moving to alternate, supplementary, or subsequent positions. Regardless of the degree of protection the route itself affords, the platoon and squads try to rehearse the movement prior to contact. Rehearsals increase the speed at which they can conduct the move and provide an added measure of security. The platoon leader makes a concerted effort to allocate available time to rehearse movement in limited visibility and degraded conditions.

INDIRECT FIRES AND OBSCURANTS

3-115. Artillery or mortar fires assist the platoon during disengagement. Suppressive fires slow the enemy and cause him to seek cover. Smoke obscures the enemy's vision, slows his progress, or screens the defender's movement out of the battle position or along his displacement route.

OBSTACLE INTEGRATION

3-116. Obstacles are integrated with direct and indirect fires. By slowing and disrupting enemy movement, obstacles provide the defender with the time necessary for displacement and allow friendly forces to employ direct and indirect fires against the enemy. The Modular Pack Mine System (MOPMS) also can be employed in support of the disengagement, to either block a key displacement route once the displacing unit has passed through it or close a lane through a tactical obstacle. The location of obstacles in support of disengagement depends on METT-TC. Ideally, an obstacle should be positioned far enough away from the defender that enemy elements could be engaged on the far side of the obstacle while keeping the defender out of range of the enemy's massed direct fires.

MOBILITY

3-117. Mobility operations in the defense ensure the ability to reposition forces, delay, and counterattack. Initially during defensive preparations, mobility operations focus on the ability to resupply, reposition, and conduct rearward and forward passage of forces, materiel, and equipment. Once defensive preparations are complete, the focus normally shifts to supporting the platoon reserve, local counterattacks, and the higher headquarters counterattack or reserve. Priorities set by the company may specify routes for improvement in support of such missions. Normally, most engineer assets go to survivability and countermobility. At a set time or trigger, engineers disengage from obstacle and survivability position construction and start preparing for focused mobility missions. The platoon leader analyzes the scheme of maneuver, obstacle plan, and terrain to determine mobility requirements. Critical considerations may include —

• Lanes and gaps in the obstacle plan.
• Lane closure plan and subunit responsibility.
• Route reconnaissance, improvement, and maintenance.

COUNTERMOBILITY

3-118. To succeed in the defense, the platoon leader integrates individual obstacles into direct and indirect fire plans, considering the intent for each obstacle group. (Refer to ATTP 3-90.4 for more information on countermobility in the defense.) Obstacles are normally constructed by engineers with help from the platoon. In the defense, the platoon or squad uses obstacles to:

• Slow the enemy’s advance to give the platoon or squad more time to mass fires on him.
• Protect defending units.
• Canalize the enemy into places where he can easily be engaged.
• Separate the enemy’s tanks from his infantry.
• Strengthen areas that are lightly defended.

3-119. Obstacle intent includes the target and desired effect (clear task and purpose) and the relative location of the obstacle group. The purpose influences many aspects of the operation, from selecting and designing obstacle sites to conducting the defense. Normally, the company commander designates the purpose of an obstacle group. When employing obstacles, the leader considers the following principles:

• Support the tactical plan. Obstacles supplement combat power, decrease the mobility of the enemy, and provide security for the platoon. While considering enemy avenues of approach, he also considers his own movement requirements, such as routes for resupply, withdrawal, counterattacks, patrols, and observation posts.
• Tie in. He ties in his reinforcing obstacles with existing obstacles. He must also tie in the obstacle plan with his plans for fires.
• Covered by observation and fire. He ensures that all obstacles are covered by observation and fire. This reduces the enemy’s ability to remove or breach the obstacles and increases the possibilities of placing fire on the enemy when he encounters the obstacle.
• Constructed in depth. He emplaces obstacles so that each new obstacle encountered by the enemy attrites the enemy force and causes a desired and controlled reaction. Proper use of obstacles in depth wears the enemy down and significantly increases the overall effect.
• Employed for surprise. An obvious pattern of obstacles would divulge locations of units and weapons. Friendly forces must avoid readily discernable, repetitive patterns.

Tactical Obstacles

3-120. The company commander assigns obstacle groups, and tells the platoon leaders and engineers what he wants to do to the enemy, and then he resources the groups accordingly. Obstacle intent includes these elements ─

• The target, which is the enemy force that the commander wants to affect with fires and tactical obstacles. The commander identifies the target's size, type, echelon, avenues of approach, or any combination of these.
• The obstacle effect describes how the commander wants to attack enemy maneuver with obstacles and fires. Tactical obstacles block, turn, fix, or disrupt. Obstacle effect integrates the obstacles with direct and indirect fires.
• The relative location is where the commander wants the obstacle effect to occur against the targeted enemy force. The commander initiates the obstacle integration process after identifying where on the terrain the obstacle will most decisively affect the enemy.
• For example, the company commander might say, "Deny the enemy access to our flank by turning the northern, mechanized Infantry battalion into our EA. Allow companies B and C to mass their fires to destroy the enemy." Scatterable minefield systems and submunitions are the main means of constructing tactical obstacles. These systems, with their self- and command-destruct capabilities, are flexible, and they aid in rapid transitions between offensive and defensive tasks. They do this better than other constructed obstacles. The force constructs conventional minefields and obstacles only for a deliberate, long-term defense. In those cases, the company and platoons usually are augmented with assets from a divisional engineer battalion. Table 3-2 shows the symbols for each obstacle effect, and it describes the purpose and characteristics of each.

Protective Obstacles

3-121. Infantry platoons plan and construct their own protective obstacles. For best effect, protective obstacles are tied into existing or tactical reinforcing obstacles. The platoon can use mines and wire, or it might receive additional materiel from company, Class IV or V supply point. The platoon also might conduct any other required coordination, such as needed in a relief in place, to recover or destroy the obstacle ─

• In planning protective obstacles, the platoon leader evaluates the potential threat to the platoon’s position. Then, employs the best system for that threat.
• Protective obstacles usually are located beyond hand grenade distance (40 to 100 meters) from the Soldier's fighting position, and may extend out 300 to 500 meters to tie into tactical obstacles and existing restricted terrain. As with tactical obstacles, the platoon leader should plan protective obstacles in-depth and try to maximize the range of his weapons.
• When planning protective obstacles, the platoon leader considers preparation time, the burden on the logistical system, the Soldiers' loads, and the risk of loss of surprise.

3-122. The three types of wire obstacles (see figure 3-11) are protective, tactical, and supplementary ─

• Protective wire can be a complex obstacle providing all-around protection of a platoon perimeter. It also might be a simple wire obstacle on the likely dismounted avenue of approach into a squad ambush position. Command-detonated M18 Claymores can be integrated into the protective wire or used separately.
• Tactical wire is positioned to increase the effectiveness of the platoon's fires. Usually, it is positioned along the friendly side of the medium machine gun FPL. Tactical minefields also may be integrated into these wire obstacles or used separately.
• Supplementary wire obstacles can break up the line of tactical wire. This helps prevent the enemy from locating friendly weapons (particularly the medium machine guns) by following the tactical wire.

Obstacle Lanes

3-123. The platoon might be responsible for actions related to lanes through obstacles. These duties can include marking lanes in an obstacle, reporting locations of the start and ends of each lane, operating contact points, providing guides for elements passing through the obstacle, and closing the lane.

Situational Obstacle

3-124. A situational obstacle is planned and possibly prepared before a mission, but it executes only if specific criteria are met. It gives the platoon leader the flexibility to emplace tactical obstacles based on battlefield development ─

• The platoon leader anticipates situations that require maneuver and fire plan modifications to defeat the threat, and considers the use of situational obstacles to support these modifications.
• By their very nature, situational obstacles must be quickly installable, but still achieve the desired effect. Therefore, scatterable mines (SCATMINEs) such as MOPMS, Hornets, and Volcanoes are the most common versions used at the platoon level. However, situational obstacles can consist of any type of individual obstacle.
• The platoon leader considers where he can employ situational obstacles. He ensures the combination of fires and obstacles are enough to achieve the obstacle effect.
• The platoon leader identifies execution triggers; situational obstacles are triggered based on friendly actions, enemy actions, or a combination of both.
• Finally, the platoon leader withholds execution of a situational obstacle until the obstacle effect is required. Once committed, those assets are no longer available to support any other mission. The platoon leader also considers that SCATMINEs have a self-destruct time. Emplacing an obstacle too soon can cause the mines to self-destruct before the enemy arrives.