Nuclear proliferation/Debate Guide

Nuclear power is a controversial topic, and some of the controversies remain unsettled, even after the facts in the article are agreed on. This Debate Guide page will provide a concise summary from each side of these unsettled issues. Much of this discussion is collected from Internet forums, and we welcome updates to provide better arguments or more reliable sources.
Many questions on proliferation are best answered in the context of specific reactor designs. See ThorCon_nuclear_reactor/Debate_Guide#Risk_of_proliferation for example.

Nuclear Weapons Proliferation: Where the Sh*t Hits the Fan

//... Still worse, nuclear industry apologists and nuclear supporters continuously pretend or deny that there is no link between nuclear energy and weapons proliferation, despite constant news and regular reports that provide evidence to the contrary. According to this CNN report, “Uranium particles enriched to near bomb-grade levels have been found at an Iranian nuclear facility, according to the UN’s nuclear watchdog, as the US warned that Tehran’s ability to build a nuclear bomb was accelerating.” This connection to the the potential for arms proliferation and ultimately nuclear war that could result in the annihilation of all life on Earth is pretty much why J.R. Oppenheimer, the father of the atomic bomb, later repelled by his own creation said, “we have become death, destroyer of worlds.” Let’s be clear, all types of civilian nuclear energy assistance raise the risks of nuclear weapons proliferation.
-- scientistswarning.org/2023/02/14/nuclear-power-a-risk-analysis
//

Response: from Captain Roger Blomquist, United States Navy (retired)] email 12 Dec 2023:
1. The US built, tested, and used its first nuclear weapons nearly 80 years ago. It is arrogant to think that we (the industrialized world) are the only ones capable of repeating those feats now. The physics cat is out of the bag. But the large majority of countries with nuclear power have no nuclear weapons. Some of them had weapons programs much earlier, but abandoned them due to cost, and confidence in the Nuclear Non-proliferation Treaty. (A few probably regretted their abandonment).

2. I believe that of the countries that did build bombs, only India had commercial nuclear power first. In other words, the proliferation has been almost entirely of the swords-to-plowshares direction rather than from commercial-to-weapons. And the nuclear weapons states rely on dedicated production reactors for weapons fissile materials because they produce “better” materials more efficiently, more quickly, and more cheaply than commercial reactors. While appropriate safeguards need to be included in any nuclear enterprise making or using fissile material, I see non-proliferation arguments as counter-productive navel-gazing.

3. Since the weapons technology is at least incompletely available to any country (especially proof that it can be done), it makes no sense for industrialized countries to foreswear a reactor type because it might make it slightly more convenient to acquire fissile materials for bombs seems like rearranging the deck chairs on the climate-change Titanic. I believe many of those who argue against a specific reactor concept on non-proliferation grounds are motivated by anti-nuclear sentiment. They are afraid that a commercial technology superior to LWRs will enable a larger, faster nuclear power buildout.

4. Non-proliferation arguments are a sophisticated-sounding way to foster an unwarranted association of nuclear power with nuclear weapons.

Blocking Diversion by "Spiking" the Fuel

There have been proposals to protect plutonium in used and re-processed fuels the same way U-235 is protected by large amounts of non-fissile U-238, impossible to separate without a large, expensive centrifuge plant. These proposals are controversial, because the physics of plutonium is different.
According to the IAEA:
// Nuclear weapons can be fabricated using plutonium containing virtually any combination of plutonium isotopes, according to advice given by nuclear-weapon States. Plutonium containing very high percentages of the isotope plutonium-239 is better suited than plutonium containing 10% or more of the isotope plutonium-240. However, even highly burned reactor-grade plutonium can be used for the manufacture of nuclear weapons capable of very substantial explosive yields. Except for plutonium created for heat-source applications containing 80% or more of the isotope plutonium-238, all plutonium is considered to be of equal "sensitivity" for purposes of IAEA safeguards in non-nuclear weapon States. // Safeguarding sensitive nuclear materials T.E.Shea and K. Chitumbo, IAEA BULLETIN, 3/1993, p.23.