for me, I would be telling you to NARROW YOUR FOCUS! A common fallacy among new thesis writiers is to try to do too much. The second thing I would tell you is that you clearly believe that you know what the answer is so you should be developing this as a hypothesis to be tested. By testing I mean that you must state your tentative conclusion in a form such that you can collect and analyze data so that it could prove your hypothesis false or wrong. If you can't disprove your hypothesis then it will stand as a firmer conclusion.

In the case of your topic, the evidence is all over the map. There are cases which support your thesis and other cases which tend to disprove it. All the caveats theat Ken mentioned apply. Here are a few sources you could look at: the 4 colonels report on El Salvador, Schwartz's Rand study of the same, Chapter 7 of Max Manwaring and my Uncomfortable Wars Revisited which refutes both studies of El Sal, my 1995 article in Low Intensity Conflict & Law Enforcement, "Little Wars, Small Wars, LIC, OOTW, the GAP, and Things That Go Bump in the Night." Also see John Nagl's Learning to Eat Soup With a Knife and Richard Downie, Learning From Conflict.

Good luck

Cheers

JohnT