Today marks the last day of America’s 60-day memorandum of understanding with Iran, which featured several nuclear provisions. Among those was an Iranian pledge not to “procure or develop nuclear weapons.” The rub, of course, is how to make sure Iran lives up to this pledge. The assumption’s been that if we can control Iran’s ability to access weapons-grade uranium, we are done.
That view, however, is challenged in the attached The Hill op-ed by Scott Kemp, a tenured MIT professor of nuclear engineering and a member of NPEC’s Board of Advisors, and Stephen Rademaker, former Assistant Secretary of State for International Security and Nonproliferation during the George W. Bush administration.
Scott helped devise Obama’s 2015 agreement with Iran. Steve has been a critic of that deal. They both agree, however, that Iran has an alternative path to making nuclear arms—mining the 200+ bombs’ worth of plutonium contained in the spent power reactor fuel at Bushehr. They believe the United States and other countries opposed to Iran getting a bomb need to do more to limit this possibility.
They make two recommendations. First, near-real-time surveillance is needed over the reactor and its spent fuel so that any attempt to divert the fuel is detected. The IAEA offers such surveillance over more than 1,000 nuclear sites globally. Iran should agree to such surveillance as well. Second, Iran should follow through on its original reactor contract with Russia to have the spent fuel removed from Bushehr.
As always, I’m curious to get your views on the attached.
As Ever,
Henry S.
PS: For more on Iran’s plutonium option, see NPEC advisory board member Greg Jones’s analysis in The Bulletin of the Atomic Scientists piece “Why do we keep ignoring the large quantity of plutonium at Iran’s Bushehr nuclear power plant?”
August 16, 2026
By: Scott Kemp & Stephen Rademaker
Iran’s other nuclear weapons option—plutonium bombs
As the conflict with Iran continues to oscillate between combat operations and diplomacy, it is worth remembering why we are doing this. The goal is to end Iran’s ability to make a nuclear weapon, and while we don’t know if diplomacy can achieve this, it is never too early to plan for success.
Plenty has been said about how Iran could build a handful of uranium bombs. Less has been said about the hundreds of bombs Iran could make using the plutonium located at its nuclear-power reactor in Bushehr. This is a major oversight.
Iran has operated the Bushehr reactor for more than 15 years. As with all reactors, plutonium has accumulated as a byproduct of normal operation, trapped inside the used reactor fuel. Some argue that extracting plutonium from the spent fuel is a sub-optimal path to a nuclear bomb, but Iran no longer has the luxury of optimal pathways. Any path might do.
For precisely this reason, that plutonium wasn’t ever supposed to be in Iran. More than 20 years ago, the Russians — who built and fueled the Bushehr reactor — promised to remove the spent fuel after it cooled and was safe to transport. The Iranians rebuffed this offer. Now, some 210 tons of spent fuel containing more than 2 tons of plutonium sits in a pool. That is enough for more than 200 first-generation weapons, compared to the approximately 10 weapons Iran could make from its stockpile of enriched uranium.
This plutonium presents a very tricky problem. It cannot be bombed, as that could create radioactive fallout with continent-scale consequences. Special forces cannot be sent to retrieve it: It is encased in hundreds of tons of highly radioactive fuel that must be carefully and methodically handled. But it certainly should not be ignored.
U.S. weapon laboratories have made clear that, even with reactor-grade plutonium, “proliferating states using designs of intermediate sophistication could produce weapons with assured yields substantially higher than the kiloton range.”
How difficult would it be for Iran to extract the plutonium to make a weapon? They would need to remove the fuel rods from the reactor’s storage pond, cut the rods open, and chemically separate the plutonium from other irradiated waste products — a step called reprocessing.
Iran has demonstrated it can reprocess at a small scale in a general-purpose hot cell. Moreover, prior studies looking at what it would take to set up a makeshift reprocessing facility suggest this is well within Iran’s ability, and could be easy to hide. North Korea did exactly this.
Could international inspectors detect these nefarious activities early enough to prevent bombs from being built? Yes, but only if they have a near continuous assessment that fuel isn’t being removed from Bushehr and sent to a makeshift reprocessing operation.
This year, the International Atomic Energy Agency has made only a single three-day visit to Bushehr in June. With such limited monitoring, Iran could easily divert and process several bombs’ worth of plutonium without anyone noticing.
There is a fix: near real-time International Atomic Energy Agency surveillance by cameras and sensors that can send data to agency headquarters on a continuous basis. Over 1,000 International Atomic Energy Agency -monitored nuclear facilities worldwide already use this type of real-time inspection. Unfortunately, the Obama administration failed to demand this as part of the 2015 Iran nuclear deal, and when the International Atomic Energy Agency later asked Iran for the same, Iran refused. This time, the U.S. should insist that Iran agree — and at the earliest possible date as a sign of good faith. Any final agreement should also require that spent fuel at Bushehr be removed once it has cooled sufficiently for transport. The Gulf States and the U.S. should open their wallets to make this happen. Russia offered to take the fuel in the past. Kazakhstan might do so as well.
Will Iran agree to these requirements? Perhaps not, but the more Iran resists these reasonable measures, the more reason there is to insist upon them. All of Iran’s neighbors, including any that may be interested in nuclear weapons of their own, will be watching to see what the United States demands — and what we agree to with Iran will set a precedent for what pathways other states are allowed to retain.
R. Scott Kemp is Professor of Nuclear Science and Engineering at MIT. Stephen Rademaker was Assistant Secretary of State for International Security and Nonproliferation during the George W. Bush administration.
To read the Kemp-Rademaker piece, click here.