A documentation and critical oral history project on 20 years of the arms race in lessons learned and unlearned for future cooperation on denuclearization. Threat Reduction Program, colloquially known as the Nunn-Lugar program after its Cooperative Threat Reduction (CTR), plan developed U.S. Senators Sam Nunn (Democrat, Georgia) and Richard Lugar (Republican, See Article History. Alternative Titles: CTR, Nunn-Lugar Cooperative Threat Reduction Program. the President praised former Democrat Senator Sam Nunn and Republican Richard G. Lugar, for the Nunn-Lugar Cooperative Threat Reduction program, Dr. Aylin G. G