No no no. To be a "trigger-puller" in the Army or the Marines (infantry, armor, artillery, combat engineer, etc.) you have to volunteer three times. Once when you decide to enlist, once when you select a service, and once when you select a military specialty. Not only do we have an all-volunteer force but you have to volunteer for training and assignment to a combat-type unit.
If you want to be in an elite unit like the Rangers or Marine Recon you to volunteer again.
Do you see how patronizing you are and how condescending? Give people some credit. Most people know exactly what they are getting into when they enlist, particularly since 9/11. All branches of the military are either exceeding or meeting their retention or enlistment quotas. Wether or not you agree with American foriegn policy or not, enlistees either agree with it or don't diasgree with it enough to keep them out of the military. It's a rational choice made by people who weigh carefully the risks and benefits.
I might as well say that many of you are applying to medical school because you can't think of anything else to do with your lives. This certainly fits for people who go straight from high school to college to medical school.