The threat of total nuclear annihilation seems to have receded since the demise of the Soviet Union. China, France, India, Israel, Pakistan, the U.K. and even Russia are U.S. allies or, at worst, nonbelligerent competitors with (Russia notwithstanding) limited nuclear arsenals. North Korea and Iran, although both enemies of the U.S., do not as yet possess the weaponry to inflict massive nuclear harm on this nation. In fact, the most pressing nuclear threat appears to be a "dirty bomb"—a conventional explosive packed with radioactive material—or a small nuclear explosive smuggled into the country.
Despite the threat reduction, however, the U.S. retains the weaponry to fight a total nuclear war: roughly 10,000 warheads and bombs. A third of these are warheads—dubbed W76—which, since 1978, have been deployed atop submarine-based ballistic missiles or stored in what is known as the Enduring Nuclear Stockpile, according to Hans Kristensen, director of the Nuclear Information Project at the Washington, D.C.-based Federation of American Scientists (FAS), an organization founded by the creators of the original nuclear weapon in 1945 that has been monitoring the nation's nuclear arsenal ever since. The W76 generates 100 kilotons of explosive force when detonated, the equivalent of 100,000 tons of the chemical explosive trinitrotoluene (TNT). It is designed to obliterate so-called "soft targets," such as ports, garrisons, or factories.
The U.S. plans to retire many of these weapons as part of its nuclear arsenal reductions under the Moscow Treaty on Strategic Offensive Reductions. But the U.S. Departments of Energy (DOE) and Defense (DOD) would also like to replace some of them. And in early March, Lawrence Livermore National Laboratory in California won the initial competition to design the nation's first new nuclear warhead in 20 years. The new weapon would not fulfill a new strategic role in a changed world, but rather replace a portion of the W76 arsenal, due to concern over the aging warheads' ability to retain their full destructive potential in storage.
A government-commissioned independent review by a panel of scientists known as JASON estimated that the plutonium primaries in the current warheads will last a minimum of a century in storage, however, and, therefore, recommended that no action be taken other than routine maintenance, such as replacing surrounding circuitry and parts as they age—a core function of the Lifetime Extension Program the W76s are currently undergoing. Despite the panel's findings and the imminent refurbishments, the Reliable Replacement Warhead (RRW) program, an effort to replace the W76 launched three years ago by the DOE to allay reliability fears, continues.
In an effort to keep the modernization program alive, the Nuclear National Security Administration (NNSA)—a a semiautonomous agency of the DOE in charge of the nation's nuclear weapons—has offered a variety of other rationales, ranging from national security to creating a more environmentally benign weapon. The U.S. Congress is now weighing the fate of the program and whether to fund it as part of efforts to determine what the U.S. nuclear arsenal will look like in the 21st century.
Same Old, Same Old?
During a press conference and subsequent interviews, NNSA officials stressed that the design for the W76 replacement warhead is not a new one. Rather, it is based on a formerly tested weapon that includes a host of new surrounding features. "It's new in the sense that we've never done this before, but it's not new in the traditional arms control sense," says NNSA's John Harvey, director of policy planning staff. "It will have the same form and function as the current weapon."
In fact, the reason the Livermore design triumphed is because it is based on a former design, one detonated underground before the U.S. moratorium on such experiments in 1992. "[The pit] was nuclear tested four times," says Bruce Goodwin, Livermore's associate director for defense and nuclear technologies. "It's the exquisite test pedigree of the baseline for this design that gives very high confidence that it will work as expected."