As long as nuclear weapons exist, the United States will maintain a safe, secure and effective nuclear deterrent to keep America safe. In support of this presidential mandate, the Energy Department — specifically the National Nuclear Security Administration (NNSA) — is responsible for ensuring the integrity and safety of the nation’s nuclear weapons, advancing nuclear nonproliferation and promoting international nuclear safety.
Established by Congress in 2000, NNSA is a semi-autonomous agency within the U.S. Department of Energy responsible for enhancing national security through the military application of nuclear science. NNSA maintains and enhances the safety, security, and effectiveness of the U.S. nuclear weapons stockpile without nuclear explosive testing; works to reduce the global danger from weapons of mass destruction; provides the U.S. Navy with safe and effective nuclear propulsion; and responds to nuclear and radiological emergencies in the U.S. and abroad.