Do we need new nukes?

The nuclear gurus are staging a comeback. Their wedge of opportunity is a technical debate that's emerged inside the weapons labs, a debate so arcane that probably only a few hundred scientists can engage its issues fully. Yet the outcome of this debate could zap new jolts of life into a vast nuclear complex—of strategic thinking, nuclear testing, warhead production, and missile deployment—that's lain moribund for more than a decade.

The spark of all this is a nuclear warhead called the W-76, the hydrogen bomb packed inside roughly 3,300 of the United States' 5,000 or so strategic nuclear weapons. Eight of them are packed inside every Trident I and Trident II missile, which are loaded into the U.S. Navy's fleet of submarines that roam the oceans, under the surface, undetectable and therefore invulnerable to pre-emptive attack. In short, the W-76 is the mainstay of America's nuclear deterrent.

When the W-76s came into the arsenal between 1972 and 1987, they were expected to have a 20-year lifespan. Most of the warheads have long passed that expiration date, and the remaining few are approaching it. So, this is the question: Is the W-76 literally obsolete? Does it work anymore? If the president pushed the button, would these bombs explode? If it seems very likely that they wouldn't, should we build a new warhead? And if we go that far, should we test it to make sure it works—that is, explode it underground and, in the process, break the Comprehensive Test Ban Treaty, which the United States signed in 1995 and started observing under the first President Bush in '92? (Every country in the world except India, Pakistan, and North Korea has signed it, though the United States and China haven't ratified it.) And as long as we're building and testing a new warhead, should we simply go with a remodeled W-76—or design something new for the post-Cold War era?

In other words, uncertainties about the W-76's reliability open a back door for a slew of nuclear weapons programs—mini nukes, bunker-busters, electromagnetic-pulse enhancers, and so forth—that critics in Congress and elsewhere have managed to block when the assault has been frontal.

Two questions need to be considered in this exercise: First, is there anything to this claim that the W-76s are duds? Second, does it matter?

The first question is complicated, but one thing is clear: The initial forecast that the W-76 would have only a 20-year lifespan is almost certainly wrong. Since the early '90s, the Department of Energy's weapons labs have put the W-76 through several elaborate modifications—new or more refined neutron generators, re-entry bodies, safety locks, arming and fusing systems, and so forth. A new round of refurbishment, called the W-76 Life Extension Program, scheduled to get under way in two years, will supposedly give the warhead an additional 30 years. (For a detailed description of all these enhancements, click here.)

Yet some veteran weapons scientists claim the W-76 had a crucial design flaw all along. The warhead was jam-packed with electronic gear, yet it had to be sufficiently small and light for eight of them to fit into a single Trident missile. As a result, the casing is very thin—so thin that, these scientists say, the slightest shockwave (say, the shock of being launched out of a submarine missile tube or separating from the missile-rocket's first stage in outer space) could disable the explosive mechanism inside; in short, the warhead would not explode with nearly enough power to destroy targets of much size or resilience. (For a slightly more elaborate explanation, click here.)

As a result, these scientists say, a life-extension program is a waste of time and money. Instead, they propose phasing out the W-76 and accelerating the Reliable Replacement Warhead, a little-known but already fast-growing R&D program. *

Which side is right on this question? The answer is probably beyond the ken of any outsider. This month, Donald Rumsfeld instructed the Defense Science Board to appoint a Task Force on Nuclear Capabilities to evaluate the controversy. But the two men named to chair the panel—John Foster and retired Gen. Larry Welch—all but predetermine its conclusions. Foster was for years the director of the Lawrence Livermore National Laboratory, which built the hydrogen bomb and most of the U.S. warheads built in the half-century since. A very intelligent and articulate scientist who has served on countless government advisory boards over the decades, Foster has long been an ardent advocate of new and more refined nuclear weapons. Welch capped his long career as the U.S. Air Force chief of staff, and in recent years has headed panels that call for accelerating missile defense and, more pertinently, expanding the lifespan of the nuclear arsenal.

In short, it's a pretty sure bet that this panel will conclude we need new warheads.