Will the world be a safer place without nuclear weapons?

JUN 22, 2010

David Kramer

A wealth of technical challenges must be overcome before President Obama’s vision of a world without nuclear weapons can ever become a reality, in the view of weapons expert Stephen Younger. And future reductions to the US nuclear stockpile will “require a lot more planning” than was necessary to conclude the New START treaty that Obama and Russian president Dmitry Medvedev signed in April, warned Younger, a former associate director at Los Alamos National Laboratory.

Younger told a Washington conference on 9 June that below some threshold—certainly at a level of 100 or fewer weapons—the US could become vulnerable to a preemptive nuclear attack. With a US stockpile that small, an enemy might calculate that it can “ride out” a retaliatory response comprising whatever is left of the US strategic force in the aftermath of the aggressive act. Younger also dismissed the commonly held assertion that a terrorist or other subnational group could design and build a nuclear weapon using information available on the Internet. “Uranium is tough stuff; try machining it,” he said. “Plutonium is the most complex material on the planet. It changes phases if you look at it.”

Apart from the unlikelihood that Russia, France, Israel, Pakistan, and North Korea would give up their nuclear arsenals, he said, there are multiple political and technical obstacles standing in the way of achieving the global disarmament that President Obama has pledged to work toward. What constitutes the dismantlement of a warhead, for example, will need to be resolved, since disassembling the weapons into their components provides no assurance of enduring nuclear abolition, said Younger. No one knows exactly how much weapons-usable material exists and where it is located. Preventing the clandestine movement of those materials or weapons may require a global network of sensors, perhaps numbering in the millions, to be installed in roads, railroads, and seaports. Designing and operating that web will be a major challenge, as will defending it both from cyberattacks and from the false alarms that may be caused by cosmic rays, Younger said.

Adding further complexity to the design of a verification regime is the fact that much of the supporting technology underlying nuclear weapons—such as high explosives, hydrodynamic codes, and processing of the nuclear and industrial materials that are used in warhead manufacture—also has legitimate non-weapons uses. No better illustration of that dual-use quandary is the ongoing dispute with Iran over the nature of its uranium enrichment enterprise.

While no-notice inspections by an international authority will be critical to verify compliance in a zero-warhead world, every nation is likely to insist that some locations—the White House, homes, and religious sites, to give a few examples—remain off-limits to those inspections, Younger said. Such challenges will require that strong R&D on new sensor technologies be maintained indefinitely. Younger, who is president of the contractor that operates the Department of Energy’s Nevada Test Site, also urged that a test bed be created where those and other verification technologies can be evaluated under real-world conditions.

Younger and others have noted that the US is alone among the world’s nuclear powers in refraining from modernizing its inventory of strategic weapons. While Congress twice rejected DOE’s request for a new warhead design known as the Reliable Replacement Warhead, Obama’s recently completed nuclear posture review leaves open the possibility of modernization, Younger noted.

David Kramer