putinAn era of unprecedented nuclear cooperation between the Cold War rivals is drawing to a close. Early this month Sergey Kirienko, who runs Russia’s state nuclear company, announced that in 2015 no new nuclear projects involving U.S. participation are “envisioned.” What transpired between the United States and Russia in the years between the end of the Cold War and the moment of this decision is the stuff of spy novels. In the aftermath of the 1991 breakup of the Soviet Union and the ensuing political chaos, the outgoing George H.W. Bush administration and incoming Clinton administration shared grave concerns about the security of Russia’s nuclear weapons and fissile materials. Their concerns were well placed. During that period I was serving at the Central Intelligence Agency, leading a group with responsibility for monitoring dire developments in Russian nuclear security. Security lapses we were able to document included gaping holes in perimeter fences around nuclear facilities, guards who refused to patrol due to lack of adequate winter clothing, and “trusted” insiders who sought to steal or divert nuclear materials for financial gain. More