The recent killing of at least eight Iraqi civilians in a shoot-out that involved Blackwater USA security guards makes this documentary on private military contractors especially timely, but it’s essential viewing for anyone who wants to understand the changing nature of war in the 21st century. Directors Nick Bicanic and Jason Bourque interviewed security executives, foreign policy scholars, journalists, and modern-day mercenaries to learn how PMCs have become an integral and problematic component of the U.S. armed forces. (In the Persian Gulf war, one in every hundred Americans on the ground was a hired gun; in the current war, the ratio is one in ten.) The film fully exposes the headache of well-paid cowboys making Iraq more dangerous for our enlisted men yet never descends into simple finger wagging, arguing instead that private armies are a fact of modern warfare and that their conduct should be regulated by the international community. 86 min. a Gene Siskel Film Center. –J.R. Jones