Lawrence Livermore National Laboratory

Nearly four decades after Lawrence Livermore was founded, the Berlin Wall was torn down, and the Soviet Union collapsed—the Cold War had been won. Today, the U.S. maintains a much smaller stockpile of weapons, but nuclear deterrence remains an integral part of its national security policy.

In 1992, President George H. W. Bush declared a moratorium on nuclear testing, and new weapons development ceased. The ending of the nuclear arms race dramatically affected the nation's three weapon laboratories—Livermore, Los Alamos, and Sandia—but their central missions still focused on national security science and technology.

In 1995, President Bill Clinton announced a new program called Stockpile Stewardship—an ambitious effort to improve the science and technology for assessing an aging nuclear weapons stockpile without relying on nuclear testing. For stockpile stewardship to succeed, all aspects of weapons must be understood in sufficient detail so experts can evaluate weapon performance with confidence and make informed decisions about refurbishing, remanufacturing, or replacing weapons as the needs arise. See video on YouTube: Stockpile Stewardship.

An Annual Assessment Review is conducted on the status of the stockpile. In this process, the secretaries of Defense and Energy receive formal evaluations of the stockpile from the three laboratory directors, the commander-in-chief of the U.S. Strategic Command, and the Nuclear Weapons Council. From those evaluations, the president makes a determination whether the weapons would perform as designed, should they ever be needed, or if nuclear testing is required again to certify performance. (See S&TR, July/August 2001, Annual Certification Takes a Snapshot of Stockpile's Health.)

Sensors and scientist inside the NIF target chamber

NIF Target Chamber

A view inside the target chamber for the National Ignition Facility (NIF), which will allow scientists to replicate various physical processes at the energy densities and temperatures approaching those in a weapon detonation.