Uranium-232, thorium… oh, and The Bulletin.

Something of a question for the readers:

Why is uranium-232, produced via a (n,2n) reaction from U-233 in a thorium breeder reactor, viewed as such a uniquely favorable impediment to diversion of material for weapons proliferation? You would expect a breeder reactor operating on a U-238/Pu-239 fuel cycle to produce some Pu-238 directly via the same (n, 2n) reaction in Pu-239 – the cross sections are about the same for fast neutrons – and Pu-238 is certainly a strong impediment to nuclear weapons use of the plutonium, as much as is U-232.

Does the Th fuel cycle actually offer some real advantage over a U fuel cycle in this regard , where the U fuel cycle does not deliver?

I suppose that the lesson to take home is that the fuels and operating conditions in power plant reactors are uniquely unfavorable for the production of weaponisable fissile materials, irrespective of the exact fuel cycle used, uranium or plutonium.

Also, the Bulletin of the Atomic Scientists seems to get a little more tabloid-like with every issue, to me at least – what’s with that?

It almost seems like every major piece in the current edition is skeptical of, cautious about, pessimistic about, wary of, or simply all out opposed to new expansion of nuclear energy in the United States and the rest of the world.