Reminds me of a film I saw. Some aging veterans (David Carradine?) rented a jet ranger and a huey and went looking for their team mates MIA. Think it ended with them finding a POW compound and busting their buddies out (while probably losing one of the rescue party, for added emotional charge).
So the missions could include:
- recon jobs to find camps in the jungle, while dodging patrols (because if you are seen it will lead to war or executions or at least the POWs would be moved)
- maybe a mission where you have to click on each prisoner through the binoculars to identify them. In the movie they were looking for specific guys, so would need to find the right prison.
- busting in to kill the guards and free the prisoners
- sneaking out across the border with rescued guys into Laos
- maybe getting back to your camp to get back in the chopper / jeeps, and find that your local scout has sold you out, so you have to hold off a wave of attackers and then form up at a new RV
- perhaps sneak back and do some sabotage of an army base to get even
- find and kill the scout for revenge (without alerting the army or police)
Or maybe it would all blow up in a diplomatic incident, and the US land troops on a beach, unload tanks, start a big shooting war, go hunting for weapons of mass destruction or whatever. But that branch in the story seems less personal and less involved with POWs.