Up to half of the$ 14 trillion spent by the Pentagon since 9/ 11 went to for-profit defense contractors, a study released Monday found.... In Afghanistan, that included contractors allegedly paying protection money to warlords and the Taliban themselves, and the Defense Department insisting on equipping the Afghan air force with complex Blackhawk helicopters and other aircraft that few but U.S. contractors knew how to maintain.... 27, 2010, file photo a private security contractor watches a NA