Guerrilla Warfare and Special Forces Operations

1. What they did

This United States Army field manual guides commanders and staff in planning and running unconventional warfare, in which small Special Forces detachments work with local resistance movements in enemy-held territory. It replaced the 1958 edition. A separate classified manual (FM 31-21A) held the more detailed techniques.

The manual is in four parts:

• Introduction: what unconventional warfare, resistance movements and guerrilla warfare are.
• Organization: how the joint task force and the Special Forces group are organized, supplied, supported with intelligence and communications, and controlled.
• Operations: infiltration by air, water and land, or staying behind as the enemy advances; building an area command of guerrillas, auxiliaries and the underground; security; intelligence; communications; logistics; combat operations; psychological operations; and demobilization.
• Appendices: references, supply, an outline for an area study and an area assessment, and terms.

2. What they found

The manual sets out guidance rather than findings. The parts most relevant to trackers deal with staying undetected, staying aware of the enemy, and planning routes.

Security (staying undetected)

• Security rests on keeping the enemy from knowing the force exists, or from finding it once they do.
• The guerrillas use two security zones. In the inner zone, guerrilla units rely on patrols, outguards and outposts, sentinels, warning devices, and cover and deception. In the outer zone, auxiliary units and the underground watch enemy movement and give early warning.
• Units stay small and dispersed, and stay mobile. Before leaving an area they remove all traces of their activity, police the area, cache what they cannot carry, and eliminate signs of the route of withdrawal.
• Camouflage discipline, careful choice and supervision of courier routes, and control of movement are enforced.
• Guerrillas memorize the locations of their installations rather than marking them on maps or papers taken out of the base.
• Moving too soon when the enemy is near can be riskier than staying hidden; the decision to move follows a careful estimate of the situation.

Awareness and warning

• Auxiliary units organize civilians who live in useful places to watch the enemy and warn the guerrillas of enemy moves.
• On the march, units are briefed on enemy activity, primary and alternate routes, and dispersal and reassembly areas. They use advance, rear and flank guards, and patrols screen each campsite before it is occupied.

Routes, terrain and maps

• Land infiltration works best in limited visibility over difficult terrain, with routes through mountains or heavy forest. It is slow, limits what can be carried, and allows routes to change as the situation demands.
• The area study outline asks for climate, terrain, relief, natural routes and obstacles to cross-country movement, drainage, vegetation and its cover and concealment, water and wild foods.
• Before infiltration, planners plot on maps or overlays: bases, drop and landing zones, landmarks and orientation points, routes and stopover sites, off-road routes, and distances between key points.

Raids and ambushes

• Withdrawal routes are planned so that pursuit is difficult; units may split into small groups and meet at rallying points.
• Ambush sites are chosen for terrain that hides the ambush and channels the enemy, with security elements on roads and trails leading in.

3. What they concluded

• Unconventional warfare depends on support from the local people and on knowledge of the area, its terrain and its population.
• Guerrilla forces survive by staying hidden, dispersed and mobile, and by early warning of enemy moves rather than by strength.
• Careful study of the area, and planning of routes and bases on maps, comes before any infiltration.

4. How tracking was or was not used

The manual does not teach tracking or trailing. Tracking appears only indirectly, from the side of those who might be followed: units leaving an area remove all traces of their activity and eliminate signs of their route of withdrawal, and withdrawal is planned to make close pursuit difficult. The manual does not say how this is done.