New Pure Fusion Nuclear
Weapons Already
Raising Major Issues
By Keay Davidson
San Francisco Examiner
Scripps Howard News Service.
A frightening new generation of "pure fusion" nuclear weapons might emerge from the construction of a new superlaser at Lawrence Livermore National Laboratory, anti-nuclear activists warn.
Unlike present thermonuclear fusion, or "hydrogen," bombs, pure-fusion weapons wouldn't have to be triggered by a fission or "atomic" bomb made from the rare, expensive elements plutonium and uranium.
Instead, pure-fusion bombs could be made so small, and with such easily obtainable elements hydrogen isotopes -- that they would dangerously blur the distinction between nuclear and non-nuclear explosives, critics say. This, they charge, would make it easier for generals or politicians to justify using nuclear weapons during wartime.
Although "immense obstacles" remain before pure-fusion weapons could be developed, their invention might be hastened by the Livermore superlaser and other new technologies variously known as "laser fusion" and "inertial confinement fusion," says a report by physicist Arjun Makhijani and his colleague Hisham Zerriffi.
They work at a leading anti-nuclear think tank, the Institute for Energy and Environmental Research in Takoma Park, Md.
"The development of pure-fusion weapons could represent as great a departure from present-day military postures as the hydrogen bomb did from fission weapons," says their report, titled "Dangerous Thermonuclear Quest: The Potential of Explosive Fusion Research for the Development of Pure Fusion Weapons," which was released last week.
A top Livermore scientist ridicules Makhijani and Zerriffi's accusations.
Rather than try to invent pure-fusion bombs, it would make more sense to drop the planned superlaser itself -- the size of a football field -- on the enemy, jokes Bill Hogan, senior scientist for the $1.2 billion superlaser project, known as the National Ignition Facility or NIF.
"In my technical opinion, I don't believe a pure-fusion weapon is feasible," Hogan says. "Even if it were, the things you learn on NIF are not going to help you to succeed in (making pure-fusion weapons)."
NIF will be used partly to investigate ways to trigger extremely small nuclear explosions, contained within a protective vessel, for the possible production of commercial electricity.
"Our laser is going to fill a football stadium. We don't see a way to(study energy generation) with a smaller (laser). If we did see a way to do it with a smaller one, we'd do it, for gosh sakes," says Hogan, a physicist with a background in nuclear weapons design.
In NIF, the idea is to repeatedly fire pellets of nuclear fuel -- the hydrogen isotopes deuterium and tritium into the containment vessel. Then lasers would fire at the pellets, like rifles aimed at skeet.
In theory, the laser firings should compress the pellets so fast that their atomic nuclei would fuse and release the energy of nuclear fusion -- ideally, the equivalent of10 to 100 pounds of high explosive.
NIF is presently under construction, and its lasers should start firing by 2001, Hogan says. Construction of the entire facility should end in 2003.
The Makhijani-Zerriffi report acknowledges the great difficulty of miniaturizing NIF-like components into a bomb. However, they suggest, eventually scientists might find a way to do so.
For example, the budding science of "nanotechnology," which tries to reassemble nature at the atomic level, might lead to new, extremely powerful explosives that could be miniaturized to compress a small container of deuterium and tritium, small enough to serve as a pure-fusion bomb. Likewise, Makhijani and Zerriffi say, recent Pentagon research could lead to "a reduction in the size of capacitors(energy-storing devices) by an order of magnitude."
Also, scientists recently reported finding a way to compress hydrogen gas until it turns into metal. Such "metallic hydrogen may also be an extremely powerful explosive" that could trigger a pure-fusion bomb, they speculate.
Hogan doesn't buy their arguments. "What you have to do to make deuterium and tritium fuse is very difficult to do: You have to raise the temperature and pressure to extreme values, those values found in the center of the sun," he says. "We've found so far only one way we believe we can do that, andthat's with these giant lasers."
And even with giant lasers, "we can only ignite an amount of (nuclear) fuel that produces (the equivalent of) 10 to 100 pounds of high explosive," Hogan says. "You'd do more damage by dropping the laser on somebody."
Hogan's joking reassurances don't impress Jackie Cabasso, a leading Bay Area anti-nuclear activist.
The Makhijani-Zerriffi study "is an important contribution to a growing body of scientific and political evidence that the nuclear weapons establishment in this country is indeed pursuing the development of new generations of nuclear weapons," says Cabasso, who works at the Western States Legal Foundation in Oakland.
Cabasso says the U.S. Department of Energy's "Stockpile Stewardship Program," which includes NIF, is a cover for the continued investigation of new designs for nuclear weapons. The Energy Department maintains that Stockpile Stewardship is needed to monitor the reliability of the existing U.S. nuclear arsenal.
Cabasso rejects Hogan's claim that the great size of NIF makes it irrelevant for weapons development. Size "isn't the point," Cabasso says. "Once fusion is achieved, then the process of miniaturizing it using other technologies becomes much more practical and there are other technologies being explored which might be very suitable (for this task), which that (Makhijani-Zerriffi) report discusses."
Pure-fusion weapons, Cabasso says, would be "particularly insidious because they may blur the distinctions between nuclear and conventional weapons, which may make them harder to (control)with treaties and make them likelier to be used."
Critics cite another objection to the development of pure-fusion bombs: A nation could more easily hide the manufacture of such bombs than of ordinary nuclear weapons. That's because the pure-fusion bombs would not require the use of uranium or plutonium, whose radioactivity can be detected by U.N. weapons inspectors.
The present way to "prevent the spread or proliferation of nuclear weapons is by detecting the materials needed to make nuclear weapons, (namely) plutonium and highly enriched uranium," Cabasso says. "Since you don't need those for pure-fusion weapons, then that means of detecting the existence of the weapons disappears."

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