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Weapons of Mass Destruction (WMD)



Defensive operations retain ground, gain time, deny the enemy access to an area, and damage or defeat attacking forces. The defense can deny the enemy victory. It cannot assure victory. The defense is a temporary state that creates the conditions that allow the force to assume offensive operations. Defensive operations are conducted to---

  • Defeat an enemy attack.

  • Gain time.

  • Concentrate forces elsewhere.

  • Control key or decisive terrain.

  • Wear down enemy forces as a prelude to offensive operations.

  • Retain strategic, operational, or tactical objectives.

Just as during offensive operations, defending forces must use NBC defensive principles--avoidance, protection, and decontamination--to preserve combat power under NBC conditions and smoke to enhance combat power.

The defensive framework consists of--

  • Security force operations forward and to the flanks of the defending force.

  • Defensive operations in the main battle area (MBA).

  • Reserve operations in support of the main defensive effort.

  • Deep operations in the area forward of the forward line of own troops (FLOT).

  • Rear operations to retain freedom of action in the rear area.

Chemical units are integrated throughout the defensive framework--

    Security. Smoke and NBC recon unit provide the security force commander versatility.

    MBA. Smoke and NBC recon units provide the commander versatility, while decon units increase the survivability of contaminated units.

    Reserve. Smoke, NBC recon, and decon units increase the survivability of reserve forces. Smoke and NBC recon units provide the commander versatility.

    Deep. Smoke and NBC recon units provide versatility and increase survivability.

    Rear. Smoke, NBC recon, and decon units assist the commander to retain freedom of maneuver and increase survivability.



Mobile Defense

Mobile defense employs a combination of offensive, defensive, and delaying actions to defeat an enemy attack. The exact design is dependent upon METT-T. In this type of defense, a small force is deployed forward in the sector and uses a combination of fire and obstacles to seize the initiative from the attacker. A force conducting a mobile defense must have the same or greater mobility as that of the attacker. The force must have a large reserve to conduct the decisive counterattack. Because of the need to have a large reserve, mobile defenses are normal y conducted by division or larger forces.

Area Defense

An area defense is normally conducted to deny the enemy access to specific terrain for a specific time. The purpose of the area defense is to retain ground using a combination of defensive positions and a small reserve. This type of defense is used when there is little depth to the sector. The exact design of this defense is also dependent upon METT-T.


Corps and division may establish a covering force as the first echelon of a two echelon function of the covering force is to destroy the leading elements of the attacking force causing the follow-on forces and forcing the enemy to disclose his main effort. The size and composition of the defense. The deployment of covering force is dependent on METT-T. Normally a covering force is organized around tank-heavy task forces and armored cavalry regiments.

Normally, the covering force will defend, delay, and attack with its maneuver units. When elements of the covering force are unable to retain terrain forward of the FEBA, they will withdraw through the element conducting the defense of the main battle area. Generally the covering force withdraws by unit.

Because of its nature, covering force elements that become contaminated probably will not undergo any supported decon operations (operational or thorough) until they have withdrawn through the MBA. If the unit must undergo decon, it will most likely be operational.

NBC reconnaissance units will provide the covering force commander with versatility. Their focus should be on determining the status (clear or contaminated) of rearward passage lanes. If they are contaminated, NBC recon units will locate and mark new clear routes.

Smoke units conceal movement of friendly forces, defeat enemy intelligence gathering efforts, and conceal the emplacement of obstacles. Smoke provides the commander with versatility and agility. Smoke is also used to support deception operations.

Chemical Brigade

The chemical brigade will plan and allocate chemical units based on METT-T. The focus should be three-fold--support the covering force, provide support to units in the main battle area, and retain a flexible and responsive chemical force in the rear area. The units in the covering force will require support in the form of smoke and NBC recon. If an ACR is used, their chemical company may require reinforcement with smoke and NBC reconnaissance assets. Most of the mechanized smoke units should be employed between the covering force area and the main battle area.

Chemical Battalion

Chemical battalions are allocated based upon METT-T. Unless there are unusual circumstances, the covering force will not require a chemical battalion HHD. The chemical battalions should be allocated to support the divisions conducting the corps main and supporting efforts. At least one battalion HHD should be allocated to control chemical assets in the corps rear. The command and support relationships of the battalions supporting the divisions are based upon providing the supported commander with sufficient versatility to prepare his defense.

Chemical Companies

If the armored cavalry regiment is deployed as the covering force, its organic chemical company also will operate in the covering force area. The ACR chemical company will deploy its NBC recon platoon based on the enemy threat of using ground contaminating chemical agents. Its focus should be on maintaining freedom of maneuver behind the units in close combat. One section should be designated to ensure the main and secondary routes to and through the MBA are clear of contamination for each squadron. The dual purpose platoon's main focus will be smoke generation. The platoon's decon equipment should be left with the company headquarters. The dual purpose platoon will provide smoke support based on METT-T. If smoke support is required beyond the scale that the dual purpose platoon can provide, the ACR company should be reinforced with mechanized smoke platoons and fuel support sections from a corps chemical battalion.

If a unit other than an ACR is conducting all or part of the covering force, that unit should be supported by a chemical company team. This chemical company team should have a NBC reconnaissance platoon, at least one mechanized smoke platoon, and a headquarters capable of providing C 2 and CSS support.

Chemical Staff Considerations

  • Focus NBC defense operations to provide the commander versatility and synchronization.

  • Operate in the lowest possible MOPP level during the preparation phase, then consider a higher MOPP for the actual battle.

  • Plan smoke to assist in breaking contact and repositioning.

  • Select decon sites throughout the covering force area.

  • Conduct operational decon operations as necessary for survivability.

  • Focus NBC reconnaissance assets on repositioning and withdrawal routes, also on passage points and passage lanes.

  • Identify alternate routes if passage routes become contaminated.

  • Designate passage points and lanes for the movement of contaminated elements.

  • Plan smoke to disrupt attacking enemy echelons.

  • Balance vulnerability of the force against the need for mass, agility, and depth.

  • The possibility of enemy NBC attacks increases just prior to the enemy attack.


The main battle area fight begins when the battle handover has occurred. The units in the MBA begin the close battle, while corps continues deep operations against the enemy's second echelon. The enemy attack will be defeated in the MBA.

Smoke is used to defeat enemy target acquisition, slow the enemy, separate and piecemeal attacking forces, and disrupt enemy command and control. Smoke is also used to obscure repositioning forces. Additionally, smoke can be used as part of deception operations. Mechanized smoke units should support maneuver forces.

NBC reconnaissance units are positioned throughout the MBA based upon the IPB. The employment of NBC recon assets will provide freedom of movement and allow the commander to reposition forces without the fear of hitting contamination. Additionally, NBC recon assets can be used to patrol the MSRs.

Decon assets are also positioned and allocated based on the IPB. Priority of decon support should be to reserve forces, fire support units, combat service support, combat support, and committed forces. Operational decon may be conducted in support of committed forces to sustain combat operations. Thorough decon sites should be established away from the major avenues of approach into the sector and outside the range of the enemy's indirect fire systems. This could be up to 20 kilometers or more.

Chemical Brigade

During the MBA fight, the chemical brigade will monitor the status of the subordinate chemical units and the NBC situation. The brigade also monitors the reconstitution efforts of the chemical units involved in the covering force area (CFA) fight.

The units conducting the MBA fight will require a mix of chemical support. Reserve forces will need NBC recon assets to allow them to move rapidly on the battlefield without undo risk from contamination. Additionally, smoke assets will allow the reserve to conceal their movement.

Chemical Battalion

Unless there is a significant change in the NBC situation, there should be little change in the employment of the chemical battalion from the CFA battle to the MBA battle. The battalions monitor the status of their subordinate units and the overall NBC situation. They identify possible situations and wargame their reactions.

Chemical Companies

The priority for CFA units is to reconstitute themselves to a fully mission capable posture. MBA units need to remain flexible. They should position themselves to best provide support. However they should avoid high-speed avenues of approach into their sectors. They must maintain communications with their higher and supporting unit's headquarters. They prepare to encounter enemy reconnaissance elements moving through the sector. If possible, these enemy reconnaissance elements are engaged and destroyed.

Selection of decon sites is coordinated with the supported unit and higher headquarters to preclude using a key piece of terrain.

Chemical Staff Considerations

  • Focus NBC defense operations to provide the commander versatility and synchronization.

  • Operate in the lowest possible MOPP level during the preparation phase, then consider a higher MOPP for the actual battle.

  • Select decon sites throughout the rear area to support the defensive scheme.

  • Identify areas that the enemy could contaminate to hinder friendly operations.

  • Focus NBC reconnaissance on repositioning and counterattack routes.

  • Plan smoke to conceal obstacle emplacement.

  • Use smoke to conceal movement of forces during mobile defense operations.

  • Balance vulnerability of the force against the need for mass and depth.

  • The possibility of enemy NBC attacks increases just prior to the enemy attack.

  • Conduct operational decon as necessary to sustain the tempo of the defense.

  • Execute thorough decon operations as necessary after the battle.

  • Plan the use of flame field expedients along dismounted infantry avenues of approach.

  • Consider the impact of enemy flame weapons on your defensive positions.


This section provides an example of how chemical units could be synchronized to support a defense. The corps mission is to defeat an attacking enemy combined arms army (CAA). The example will use the defensive framework and is only one example of a concept and should be treated as such. The corps portrayed in this example consists of one armored division, one mechanized division, a separate mechanized brigade, an armored cavalry regiment, an aviation brigade, and the associated combat support and combat service support units. A chemical brigade with all the subordinate chemical units for this size force are present and available for employment (Figure 8-1). The attacking enemy CAA consists of three motorized rifle divisions in the first echelon and two tank divisions in a staggered second echelon. The first echelon division will attack with two regiments in their first echelon and two regiments in their second echelon. The enemy has an extensive chemical weapons capability and a limited nuclear capability. He has used chemical weapons extensively during both defensive and offensive operations. No nuclear weapons have been used.


The mission of the corps is to defeat the attack of the first echelon of the CAA. Following the defeat of the CAA, the corps will either reestablish the defense to defeat the second echelon of the CAA or attack as part of a counteroffensive. Both of these sequels could be conducted. The corps commander's intent is to defeat the CAA with a mobile defense throughout the depth of the MBA.

The MBA units will defeat the first echelon divisions and shape a penetration of the CAA's tank division. The corps reserve will attack into the salient created by the penetration to destroy the tank division. The corps commander envisions that the CAA will be defeated if the three lead motorized rifle divisions and one of the second echelon tank divisions are destroyed.


The corps covering force, the 201st Armored Cavalry Regiment augmented with two balanced task forces, will fight to destroy at least 50 percent of the lead regiments in the first echelon division. Following battle handover, the MBA units will defeat the attrited first echelon divisions in the MBA. The 313th Infantry Brigade (Separate) on the right will defeat the enemy division forward of PL Gold, while the 52d Infantry Division (Mech) on the left voluntarily shapes a salient back to PL Gold to draw in the lead second echelon tank division. The corps reserve, the 23d Armored Division, will then counterattack into the salient to destroy the enemy tank division. The corps defense will then be reestablished with both divisions and the separate mechanized brigade along a newly defined FEBA (Figure 8-2).


The corps commander's guidance on chemical support is to--

  • Provide the covering force with smoke support to ensure their success.

  • Allocate and position NBC recon systems to facilitate maneuver with priority to the covering force, then the MBA forces.

  • Accept risk in the covering force area against chemical strikes. I don't want to conduct any decon operations in the covering force unless I have no choice.

  • I want the corps reserve to have sufficient smoke support to conduct their counterattack.

  • The priority of chemical support is to the main effort.

Table 8-1 shows the available and committed chemical units supporting the corps for this operation. The committed chemical units are those already performing support missions or those assigned to the corps subordinate units. The available forces are those that have not been assigned missions for the upcoming operation.

The chemical brigade commander assisted by the corps chemical staff officer and the chemical brigade S3 develop a scheme of support. This scheme of support is approved by the corps commander and is executed by the chemical brigade. The approved concept is to--

  • Support the 201d ACR (corps covering force) with a mechanized smoke company (attached).

  • Support the 52d ID (corps main effort) with a chemical battalion (OPCON) consisting of a mech smoke company and a motorized smoke company.

  • Support the 23d AD (corps reserve) with a chemical battalion (OPCON) consisting of a motorized smoke company and a mechanized smoke company (this smoke company is initially with the covering force).

  • The remaining chemical assets support the corps rear area. The remaining chemical battalion will have an area support mission.


The 52d ID is the corps main effort. The division has the mission to defend from PL Blue to PL Gold. The division will defeat the attrited first echelon division and voluntarily shape a salient back to PL Gold to draw in the lead second echelon tank division. The division will hold the enemy tank divisions penetration forward of PL Gold, while the armored division attacks into the left flank of the enemy tank division.

The division will defend with three brigades abreast; 2d Brigade on the left, 1st Brigade in the center, and 3d Brigade on the right. The 1st Brigade is the main effort and will conduct a mobile defense from PL Blue to PL Gold to draw the enemy second echelon tank division into Objective Red. The 2d and 3d Brigades will hold the shoulders of the penetration. 3d Brigade will assist the passage of the corps reserve through their sector for the counterattack. The division reserve will be the aviation brigade augmented by a mechanized task force (Figure 8-4).

The division commander provides the following guidance on the employment of chemical assets--

  • Give the supporting efforts (2d and 3d Brigades) smoke. I want to obscure the preparation of the defense in those sectors and let the enemy see the defensive work in the center. I want to show strength on the right and left flanks so he'll go in the center.

  • Priority of NBC recon is to the 1st Brigade so he can maneuver freely to shape the penetration.

  • My priority of decon is to the FA. I want them to keep up throughout this operation.

  • I will accept risk during the MBA fight.

The division chemical officer and supporting chemical battalion commander developed the recommended scheme of support (Figure 8-5). The division commander approves the recommended plan. The division chemical company will be OPCON to the chemical battalion. The chemical support plan for the division is--

  • Support 1st Brigade (main effort) with two NBC recon squads (four vehicles), their habitual decon platoon, and the divisional smoke platoon in DS.

  • Support 2d Brigade with a mechanized smoke company and a decon platoon in DS.

  • Support the 3d Brigade with a motorized smoke company, a decon platoon, and an NBC recon squad (two vehicles) in DS. The NBC recon squad will ensure the freedom of maneuver of the corps counterattack force through the brigade sector.

  • The heavy division chemical company (-) with its fourth decon platoon is in GS with the mission of providing decon support to half the division rear.

  • The chemical battalion TOC will position itself near the division main CP.


The 2d Brigade has the mission of defending in sector from PL Blue to PL Gold. The brigade will hold the left shoulder of the planned penetration into the 1st Brigade's area. The brigade is task- organized with two mechanized infantry battalions, a tank battalion, a combat engineer battalion in DS, a field artillery in DS, along with the typical slice of division troops. The division has given the brigade a mechanized smoke company and a decon platoon in DS (Figure 8-6).

The brigade commander's scheme of maneuver is to defend with the mechanized heavy TFs forward in battle positions. The balanced TF is the brigade reserve with a counterattack mission. The brigade commander provides the following guidance on the employment of the chemical assets--

  • I want to obscure the emplacement of the obstacles with smoke, but the engineers have to be able to see what they're doing.

  • After supporting the obstacle preparation effort. I want the smoke company to be prepared to support the counterattack.

The brigade chemical officer works with the smoke company commander to develop a recommended chemical support plan (Figure 8-7). They work closely with the brigade S-3. The chemical support plan is approved by the brigade commander. The chemical support plan for the brigade follows--

  • The smoke platoons will operate on an area basis to create a series of smoke hazes across the brigade's sector. As the covering force withdraws, the smoke company will cease smoke operations on order from the brigade commander in close coordination with the covering force commander. The smoke company then withdraws to the BSA to refit. After refitting, the smoke company will link up with the brigade reserve. The smoke company is prepared to support the reserve when it counterattacks with hasty smoke Support.

  • The decon platoon will be positioned in the brigade support area (BSA) with a be-prepared mission of conducting thorough decon. This platoon and/or a corps decon platoon may be called on to decon portions of the covering force as it withdraws through the brigade area.

  • The decon platoon will receive class I and III support from the forward support battalion in the BSA. The smoke company will draw all its support from the designated corps support group. The smoke company and the decon platoon will monitor the brigade's operations and intelligence (O&I) net.

  • The smoke company commander will provide situation reports to the chemical battalion commander via MSE every four hours. The smoke company commander will tune in to the smoke platoon internal nets to monitor, request information, or pass instructions.

  • Once the smoke company links up with the reserve, the company will monitor the TF's command net.

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