...The existence of a zone of de facto impunity for killings by private contractors operating in Iraq and elsewhere has been tolerated for far too long. Government officials with whom I met acknowledged this lack of accountability, and it now seems to be recognized that this vacuum is neither legally nor ethically defensible...Indeed, many of the contractors themselves now accept the need for legal regulation and accountability. It is also encouraging that the US has participated in...the Swiss Initiative on Private Military and Security Companies...However, the principle problem today is that US prosecutors have failed to use the laws already on the books to prosecute contractors.