Contractors are deeply intertwined with the American military and U.S. foreign policy. Over half of the personnel the United States has deployed in Iraq and Afghanistan since 2003 have been con- tractors. Their relationship with the U.S. government, the public, and domestic and international law differs from that of military personnel, and these differences pose both bene½ts and risks. America's use of private military and security companies (PMSCs) can provide or enhance forces for global gover- nance. Yet PMSCs can also be used to pursue agendas that do not have the support of American, inter- national, or local publics. Thus far, the use of PMSCs has proved a mixed bag in terms of effectiveness, accountability, and American values. Moving forward in a way that maximizes the bene½ts of contrac- tors and minimizes their risks will require careful management of the uncomfortable trade-offs these forces present.