Almost all the contractors are former military. It's a fucked up business, I used to be a defense contractor. You go into the Military first, on Uncle Sam's dime, get tons of training and experience, then after your first enlistment, you go become a contractor, keep your skills and whatever else you picked up along the way, and get double the pay you were getting before, however, usually benefits and job security are shit, that's the deal.

Meanwhile, the pay and benefits you get as a contractor are nothing compared to what your company gets, as you only get a fraction of that--It is way more expensive to the tax payer to use contractors than hire directly, however dumb-ass politicians who want to shrink the size of the government do it by shifting that work load to the "private sector" who usually does a terrible job anyways. It's all a huge scam on the public. The federal government is nearing modern era all-time lows in per capita employment as they continue to shift money to belt-way bandits.