David Galula wrote the bible on counter-insurgency warfare. Trained at the French military academy at Saint Cyr, Galula saw conventional warfare action in World War II, then spent the remainder of his career fighting guerrillas and insurgents from Africa to Indochina. In 1961, he published "Counter-Insurgency Warfare: Theory and Practice". The book is 99.98% about tactics, and 0.02% about equipment, which tells you something about the nature of counter-insurgency.
He lived to see his careful instructions ignored by US military planners in Southeast Asia. This was a pattern tragically repeated by US military planners in Southwest Asia.
Galula limits his guidance on equipment mostly to three main paragraphs, with a heading entitled: "Adaptation of the Armed Forces to Counter-Insurgency Warfare".
Defense Tech recently has discussed whether the US military needs its own counter-insurgency aircraft fleet, provoking quite a bit of informed discussion. To keep the conversation going, it's probably a good idea to read what the master says. To wit:
"As long as the insurgent has failed to build a powerful regular army, the counterinsurgent has little use for heavy, sophisticated forces designed for conventional warfare. For his ground forces, he needs infantry and more infantry, highly mobile and lightly armed; some field artillery for occasional support; armored cavalry, and if terrain conditions are favorable, horse cavalry for road surveillance and patrolling. For his air force, he wants ground support and observation planes of slow speed, high endurance, great firepower, protected against small-arms ground fire; plus short takeoff transport planes and helicopters, which play a vital role in counterinsurgency operations. The navy's mission, if any, is to enforce a blockade, a conventional type of operation that does not require elaboration here. In addition, the counterinsurgent needs an extremely dense signal network.
"The counterinsurgent, therefore, has to proceed to a first transformation of his existing forces along these lines, notably to convert into infantry units as many unneeded specialized units as possible.
"The adaptation, however, must go deeper than that. At some point in the counterinsurgency process, the static units that took part initially in large scale military operations in their area will find themselves confronted with a huge variety of nonmilitary tasks which have to be performed in order to get the support of the population, and which can be performed only by military personnel, because of the shortage of reliable civilian political and administrative personnel. Making a thorough census, enforcing new regulations on movements of persons and goods, informing the population, conducting person-to-person propaganda, gathering intelligence on the insurgent's political agents, implementing the various economic and social reforms, etc. -- all these will become their primary activity. They have to be organized, trained and supported accordingly. Thus, a mimeograph machine may turn out to be more useful than a machine gun, a soldier trained as a pediatrician more important than a mortar expert, cement more wanted than barbed wire, clerks more in demand than rifleman."
-- Stephen Trimble