Here is some interesting information regarding the comments that suggest the military is mostly formed of the poor and lower ranks of society.
http://www.usatoday.com/news/opinion...ier-edit_x.htm
According to a comprehensive study of all enlistees for the years 1998-99 and 2003 that The Heritage Foundation just released, the typical recruit in the all-volunteer force is wealthier, more educated and more rural than the average 18- to 24-year-old citizen is. Indeed, for every two recruits coming from the poorest neighborhoods, there are three recruits coming from the richest neighborhoods
If, for example, we consider the education of every recruit, 98% joined with high-school diplomas or better. By comparison, 75% of the general population meets that standard. Among all three-digit ZIP code areas in the USA in 2003 (one can study larger areas by isolating just the first three digits of ZIP codes), not one had a higher graduation rate among civilians than among its recruits.
In fact, since the 9/11 attacks, more volunteers have emerged from the middle and upper classes and fewer from the lowest-income groups. In 1999, both the highest fifth of the nation in income and the lowest fifth were slightly underrepresented among military volunteers. Since 2001, enlistments have increased in the top two-fifths of income levels but have decreased among the lowest fifth.