A persistent myth told again and again by those opposed to the war is that we rely on the poor and stupid to fight.
The poor are actually under-represented because they don't enlist and the stupid can't qualify to serve. Indeed, the better off are enlisting in greater numbers as time goes on.
Just some of the information in this short piece by the Pentagon.
Not that the facts will get in the way of a good story about how the poor and minorities are unfairly shedding blood for our country. I guess when nobody you know has a family member or friend serving in the military it is easier to believe you are typical of America while the military is not.