They take positions on high mountain ridges and watch the patrols moving about on valley floors and off into the distance. They use high-powered binoculars to gather basic intel on the Americans. How many, where, which direction they are heading, how heavily armed are the patrols. They power their communication equipment with simple car batteries.
When they are spotted from below or from the air above, these groups of two or three men slink away into caves or crevices until the search for their whereabouts moves on to another area.
The terrain they work in is inhospitable, dry, arid, scorching during the summer months. The work they do is invaluable to the others in their cause. Their intelligence can play a key role in the success of any mission launched by their compatriots. Yet, when they die from heat or starvation or the elements, they are quickly replaced by others eager to fill their sacrificial roles.
Nope, wrong war. How about Arizona and the US war on drugs.