Congress passed the Nunn-Lugar amendment, authorizing U.S. threat reduction assistance to the former Soviet Union, in November 1991, after a failed coup in Moscow and the disintegration of the Soviet Union raised concerns about the safety and security of Soviet nuclear weapons. The annual program has grown from $400 million in the DOD budget around $1.1 billion across three agencies DOD, DOE, and the State Department. It has also evolved from an emergency response to impending chaos in the Soviet Union, to a more comprehensive threat reduction and nonproliferation effort, to a broader program seeking to keep nuclear, chemical, and biological weapons from leaking out of the former Soviet Union and into the hands of rogue nations or terrorist groups. The Department of Defense manages the Cooperative Threat Reduction (CTR) Program, which provides Russia, Ukraine, Belarus, and Kazakhstan with assistance in transporting, storing, and dismantling nuclear, chemical, and biological weapons. U.S. assistance has helped these nations eliminate the delivery systems for nuclear weapons under the START I Treaty, secure weapons storage areas, construct a storage facility for nuclear materials removed from weapons, construct a destruction facility for chemical weapons, and secure biological weapons materials.