4,000 stockpiled U.S. nuclear warheads*

In a world that possess more than 10,000 nuclear weapons, the U.S. maintains a stockpile of more than 4,000 nuclear warheads. The Stockpile Stewardship program ensures the safety, security, and reliability of these warheads without nuclear testing. Livermore’s expertise in high-energy-density science, high-performance computing, and nuclear and isotopic science, combined with unique research facilities, meet the formidable technical challenges of ensuring that the nuclear deterrent remains effective.