President Obama thanks Sen. Nunn and Sen. Lugar for their work President Barack Obama thanks former Georgia Sen. Sam Nunn and Indiana Sen. Richard Lugar for their work to help denuclearize countries after the fall of the Soviet Union during a ceremony at the National Defense University in Washington, D.C., on Dec. 3, 2012. The Cooperative Threat Reduction Program, established in 1991 as part of the Nunn-Lugar Act, is a critical part of the U.S. approach to reducing the threat of proliferation of weapons of mass destruction and related materials. SHARE: Download: Full Size (0.05 MB) Credit: VIRIN: 316127-S-GJY78-171.jpg Photo Gallery