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
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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 of Plutonium 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.
ThorCon_nuclear_reactor#Weapons_Proliferation
Integral_Fast_Reactor#Weapons_Proliferation
Chapter 19: You Can't Get There From Here, in Earth is a Nuclear Planet, Mike Conley & Tim Maloney, 2024.
"The plutonium isotopes used in fuel are hopelessly blended together, rendering it useless for weapons."
"With such a wide array of plutonium isotopes in used fuel, ranging from Pu-238 to Pu-243 and beyond, there is no practical way to isolate Pu-239 from its isotopic brethren."
"The concentration of Pu-239 must be greater than 10:1 to make a weapon."

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.
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Statement from Dr. Gordon Edwards, President, Canadian Coalition for Nuclear Responsibility, email Mar 25, 2024:
// Those advocating civilian reprocessing of some kind routinely make certain assertions that have been discredited by authorities who are generally more knowledgeable about the fabrication of nuclear weapons than the civilian reprocessing advocates are. These include (1) the assertion that not all types of reactor-produced plutonium can be used for the fabrication of reliable, highly effective nuclear weapons; (2) the assertion that weapons-usable materials can be rendered proliferation-resistant if they are mixed with the “minor actinides” (actinides with atomic numbers 93, 95 and higher). Both of these assertions have been discredited by authorities connected to nuclear weapons programs.
- Explosive Properties of Reactor Grade Plutonium J. Carson Mark, Science & Global Security, 1993, pp.111-128.
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Excerpt from a paper by Richard L. Garwin, Senior Fellow for Science and Technology, Council on Foreign Relations, 26 August 1998:
// The nations signing the NPT, and the nuclear power industry worldwide, would be delighted if plutonium produced by nuclear reactors that operate to generate electrical energy were not usable to make nuclear weapons, but the facts are otherwise, as explained in the previous paragraphs. Nevertheless, some interpret their own wishes as the facts; and beyond those who are confused in this fashion there are advocates and publicists (either without the ability to form their own judgment or who do not recognize the responsibility to do so) who repeat arguments that-- if true-- would cut one possible link between nuclear power and nuclear weapons.
- Reactor-Grade Plutonium Can be Used to Make Powerful and Reliable Nuclear Weapons Richard L. Garwin, 26 August 1998.
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Is Thorium Non-proliferating?

This video by John Kutsch, Executive Director of the Thorium Energy Alliance says YES.
"There is not one bomb that's been made in the last 60 years that uses thorium."
"The reality is nobody is ever going to turn thorium into a weapon EVER because history is the proof."

Comments by Kirk Sorensen, President and Chief Technologist, Flibe Energy, starting at 13:34 in LFTR (Liquid Fluoride Thorium Reactor) Defended by Kirk Sorensen @ ThEC2018 YouTube

"[LFTR] fully embraces the idea that we are going to do [online chemical processing]."

"The fuel that [LFTR] runs on, U-233, was investigated and rejected for nuclear weapons over and over and over again … so we have almost 80 years of history to go on now."

"People could have used this for nuclear weapons and didn’t. If a country wants nuclear weapons, [there are many ways] to get them a whole lot easier. It’s going to make no difference whatsoever whether or not we build a thorium reactor."

"[In monitoring diversion of fissile materials] a chemical processing system actually works to your advantage, because it helps you know what’s in [the salt]."

"You are going [to have] some kind of chemical processing system in any MSR, just to keep impurities out, just to keep oxides and sulfides out. We [can’t] build a molten-salt reactor with no chemical process."

"There are many countries that have successfully utilized chemical reprocessing of nuclear fuel, that do not have nuclear weapons … such as Japan and Germany."

"You can do chemical processing of nuclear fluids, and it has nothing to do with proliferation. If a country wants to have nuclear weapons, they are going to get them, and they are sure as heck not going to use a molten-salt reactor … They’re gonna build a graphite natural uranium pile, just like everybody else did, or they’re just gonna enrich uranium to highly enriched levels. But they’re not gonna go and surreptitiously rob a reactor to obtain materials for a nuclear weapon. I’m sorry, it’s just absurd."

Answer: from Tom Ledbetter’s little lesson in nuclear proliferation prevention
…“a 1 GWe plant would generate the material for a bomb every week, although you could not use that; instead you could siphon off the material for a bomb every 16 weeks (with a BR of 1.06) and still maintain your reactor running tip-top.” … “If that doesn't scare you, you're insane. Literally.”

Discussion:
See the FaceBook forum Renewable vs Nuclear Debate for ongoing discussion. Open questions:

• Can U-232 serve as a "denaturant" for the U-233 fissile produced from the thorium?
  
• Is it possible, with minor modification of a thorium reactor, to produce weapons grade U-233 without U-232?
  

What about Moderately Enriched Uranium MEU-20%?

• Will production and shipping of large quantities of 20% U-235 (HALEU in industry jargon) increase the risk of diversion?

Old generation reactors run on Low Enriched Uranium LEU-5% or less. Some of the newer designs need 20%. Enrichment from 20% to weapons grade is less work than starting with 5%. Is that a significant difference?

Iran's pursuit of nuclear weapons

This is a counter-example to the general trend that weapons are developed before nuclear power. It appears that the Iranians succeeded in diverting plutonium from a power reactor. Here is the story from ThorCon's Safeguards paper.

// The Iranians in October 2012 shut down the Bushehr pressurized water reactor after only 60 days operation, and pulled the fuel elements.[3] The removal period was said to be Oct 22 to 29. WSJ received estimates of 10 to 100 kg of Weapons Grade plutonium in these fuel elements.4 After a long silence, the shutdown was blamed on “stray bolts” that had fallen to the bottom of the reactor vessel. The dropped bolts story was later denied by the Russians who said the shutdown was for “safety testing”. Others claimed it had to do with the handover from the Russians to the Iranians. The US and others protested, but did nothing. The assumption presumably was that the Iranians do not have the capability of separating the plutonium from the fission products. Maybe, but we can be confident they have a supply of Weapons Grade Pu waiting for the day they do. In mid-2013 the Bushehr reactor resumed operation.
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