In a time of budget cuts and shifting priorities (a Democratic-controlled government more interested in supporting entitlement programs and less interested in providing enough dollars for the defense of the nation) the Department of Defense (DoD) has to use unique measures to attain its objectives across the world. A large standing army is not necessarily the best approach to providing security to third world and developing nations in a constrained economic environment. In addition to the fact that large conflicts cost money (and lives) the DoD has come to the realization that we probably are better off letting other nations fight their own wars.
One way of achieving the objectives above is to train and advise countries around the world (ones friendly to us) in matters of the military. In order to accomplish this DoD has been pushing the Security Force Assistance (SFA) concept - where teams of trainers and advisers go overseas and work with the militarys of other countries to help them become more professional and competent in order that they be able to solve their own security problems. One example of SFA is in Afghanistan where Security Force Assistance Advisor Teams or SFAATs are advising the Afghan National Security Forces (ANSF).
Derek S. Reveron, a professor of national security affairs at the US Naval War College, has wrote an article about the DoD's Security Force Assistance program. You can read it here on the Atlantic Council's New Atlanticist Policy and Analysis Blog. See "Defense Reduction through Security Force Assistance" published on February 8, 2013.