Pure fusion weapon

A pure fusion weapon is a hypothetical hydrogen bomb design that does not need a fission "primary" explosive to ignite the fusion of deuterium and tritium, two heavy isotopes of hydrogen used in fission-fusion thermonuclear weapons. Such a weapon would require no fissile material and would therefore be much easier to develop in secret than existing weapons. Separating weapons-grade uranium (U-235) or breeding plutonium (Pu-239) requires a substantial and difficult-to-conceal industrial investment, and blocking the sale and transfer of the needed machinery has been the primary mechanism to control nuclear proliferation to date.^[1]

^ Davidson, Keay (1998-07-20). "Activists: Super-laser may bring tiny nukes". San Francisco Chronicle. Critics raise 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. The reason is that pure-fusion bombs would not require 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."

[SFC_1-1] Davidson, Keay (1998-07-20). "Activists: Super-laser may bring tiny nukes". San Francisco Chronicle. Critics raise 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. The reason is that pure-fusion bombs would not require 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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