Theodore Postol is a retired MIT physics professor who was a consultant to the Pentagon on nuclear weapons and missile defense. He recently published a presentation on Iran’s nuclear weapons capability, which he summarized in a YouTube interview. Professor Postol explains, in considerable detail, how the construction of a deliverable fission bomb is well within the capabilities of Iran. His full presentation .PDF is available here, and I will show some of the key slides. Curiously,this information has not been reported in the mass media. I will explain why this is a big story, and why it has been suppressed.
How Iran Can Build a Bomb
To make an operational nuclear weapon, Iran needs three things:
1. Fissile material
Using information gathered by the International Atomic Energy Association (IAEA) monitoring Iran’s nuclear activities, Professor Postol lays our a chain of reasoning starting with the current stockpile of 60% enriched U235 and ending with the creation of bomb-grade U235 sufficient for making multiple fission bombs. There is no evidence that the 60% enriched material was destroyed during the recent attacks by Israel and the U.S., and Iran would have been highly motivated to securely store this relatively small quantity of material.
Postol July 24, 2025 presentation page 2
A key point of this presentation is that Iran’s existing stockpile of 60% enriched U235 can be further enriched to a weapons grade of 83.7% with a fraction of the resources required to perform the original enrichment from U238, and that the production facilities needed would easily fit in a small commercial building.
2. A compact bomb design
The simplest design for a nuclear bomb uses U235 and creates a critical mass by very rapidly joining sub-critical portions of the fissile material by explosive means. This was the method used in the atomic bomb that the U.S. dropped on Hiroshima. The physics determining the results are so straightforward that no testing is required. The explosive yield of a missile-deliverable rudimentary warhead of this type is relatively low (10-20 kilotons) compared to plutonium fission or thermonuclear weapons, but it is sufficient to destroy a city.
Postol July 24, 2025 presentation page 27
Postol July 24, 2025 presentation page 28
Postol July 24, 2025 presentation page 30
The estimated explosive yield of the bomb design described by Professor Postol, 7 to 20 kilotons, would be roughly equivalent in destructive power to the bomb dropped on Hiroshima in 1945 (15 kilotons). Hiroshima’s population at that time (350,00) was roughly the same size as that of present day Haifa (290,00).
3. An effective delivery system
Iran possesses multiple missile systems capable of delivering a 100 kg nuclear payload from Iran to Israel, including Sejjil-2, Khaybar Shekan, Fattah, and Dezful. All of these enable nuclear warhead delivery and have additional payload capacity for decoys to counter interceptor missiles. Maneuvering and hypersonic designs (e.g., Khaybar Shekan and Fattah) further complicate Israeli defenses.
Strategic Implications of an Iranian Bomb
The main value for Iran of having a nuclear weapons capability is deterrence. Israel can no longer threaten Iran with complete destruction through nuclear attack or a full-fledged U.S. ground invasion. Even a few nuclear missiles could entirely devastate Israel and inflict unacceptable casualties on U.S. forces in the region.
While Israel has a sophisticated civil defense system oriented toward conventional and chemical missile threats, it lacks the infrastructure to protect the general population from radiation exposure following a nuclear attack. There are limited radiation-hardened shelters, no mass fallout protection for urban populations, and no publicly disclosed national-scale radiation response system. Israel’s nuclear defense strategy leans heavily on deterrence and interception, not population shielding against nuclear aftermath.
A 10-kiloton nuclear detonation over Tel Aviv could cause up to 100,000 immediate deaths and half a million total casualties, while a strike on Haifa could result in 40,000–70,000 deaths and 300,000+ injured, especially if industrial zones are hit. These are conservative estimates; actual numbers could be higher depending on detonation specifics and emergency response capability. The economic, environmental, and geopolitical consequences would be catastrophic. Nuclear strikes against Iran by Israel would be similarly horrific.
The possibility of an Iranian nuclear strike nullifies Israel’s conventional missile defense doctrine of only intercepting missiles projected to strike populated areas or critical infrastructure. While such selective engagement conserves interceptor resources during conventional attacks, it becomes untenable when facing a potential nuclear threat. Even a low-yield nuclear detonation causes widespread destruction — including blast damage, thermal radiation, EMP, and fallout — far beyond a single impact point, making any missile that enters national airspace a strategic threat. In this context, all incoming ballistic missiles must be treated as potentially nuclear-armed, regardless of their projected trajectory. This necessitates full engagement of all targets, regardless of whether they appear to threaten specific structures. As a result, the presence or even the suspicion of nuclear warheads dramatically increases the burden on missile defense systems and undermines any defense strategy based on triaging perceived risk.
It is likely that Iran will follow the example of Israel and refuse to declare its possession of nuclear weapons. This will shield the program somewhat from criticism, but enough information will be leaked or discovered to make the nuclear capability credible. It is a sad irony that aggressive military action to prevent Iran’s development of a nuclear weapon may have finally convinced Iran that such a development is necessary.
The Silence of the Sheep
The absence of commentary in the mainstream media on Professor Postol’s declaration of an Iranian nuclear capability can be explained mainly by the timidity of today’s mass media. Reporting this story would make Trump’s declaration of ending Iran’s nuclear program appear foolish. This could trigger punitive action by the Trump administration against the business interests of the media owners. Editors and journalists may conceal their political fears by declaring that there is no confirmation of Postol’s assertions by the U.S. intelligence community, but this is the same community that has been spinning like a weather vane in the political winds, alternately confirming and denying Iran’s nuclear weapons program for years.
Conclusion
Based on Professor Postol’s arguments, it is very likely that Iran either already has a deliverable nuclear weapon, or that it could produce one in the very near future. This development means a dead end for Israel’s strategy of eliminating Iran as a regional adversary. Israel will not be able to persuade the U.S. to invade a nuclear-armed Iran, and Israel will no longer be able to threaten Iran with a nuclear strike without fear of nuclear retaliation. The misguided militaristic foreign policies of Israel and the U.S. have resulted in another instance of nuclear weapons proliferation, and more will likely follow as long as these nations persist in using military force as their primary geopolitical tool. If Israel and the U.S. continue to live by the sword, they will find nuclear swords appearing in the hands of other nations.
So what. If I’m not mistaken, Iran has not attacked anyone not in self-defense since Shah Abbas the great. We should be more concerned about the US and Israel having nukes.
As far as I understood the matter,( possibly not that much, especially the technological part ) ,another MIT teacher seems to have a different opinion.
His rant , published on June 16, can be read here :
https://contropiano.org/news/scienza-news/2025/06/16/sul-nucleare-iranino-sterminati-branchi-di-castronerie-0184130
Caveat: I’m no expert on nuclear (or other) weapons, but it seems that the counterpoint chap is saying that the Iranians do not have the wherewithal for a fusion (i.e. thermonucear) weapon, whereas Postol is saying they can readily make a U-235 fission weapon. If I’m misunderstanding, correction / clarification is warmly invited.
Honestly, it seems to me the Iranians would have to be mad to not have a nuclear weapon, but if you *do* have one, it seems to me you want all and sundry to know.
Never underestimate the power of stupid, in both Israel and the US. Both in the new century have consistently underestimated groups and nations they regard as adversaries. So far our ruling elites have managed to drive Russia and China closer together, turned Russia’s military into the most capable on the planet, and alienated 4/5 of the planet’s inhabitants with their perennial war-mongering and genocides. Netanyahu and the crazies who surround him may now think a preemptive nuclear strike will solve their Iran problem (while calling Pakistan’s bluff in the process). Alternatively, Israel might use a false flag event to draw the US into an all-out war with Iran. And should we lose 2 carrier groups to Iran’s hyper-sonic missiles in the ensuing conflict, who doesn’t think Trump, listening to the rabid warhawks in the GOP like Lindsay Graham, won’t go nuclear?
The thing that frightens me, is that even if Iran has developed nuclear warheads, you might have a US president or Israel launching a first-strike nuclear attack on Iran thinking that they can cripple Iranian nuclear launch capability or win a nuclear war on the basis of “we have more nukes than they do” which inevitably leads to a world nuclear exchange. Neither the US or Israel is run by rational or forwards thinking people, and even if Trump or Netanyahu leave office, they will be replaced by somebody else with the same worldview regardless of party.
It is amazing how one person in office can force all of the other citizens of a country to be dragged along with his decisions on a whim regardless of what the majority wants despite the fact that modern Democratic Republics are supposed to prevent this very thing from happening.
I suppose all of the flowerly language and romanticism surrounding “democracy” do not mean much when many world leaders can just override any sort of legality with the mentality of “Because I said so, and the law is what I say it is!” and realistically, nobody will stop them in most cases.
There’s this weird bit where the intelligence community loudly says all sorts of scary things about Iran’s nuclear program and then quietly says, “don’t worry.”
The National Intelligence Estimate for 2007 says Iran abandoned nuclear weapons development and every year’s NIE since has said they aren’t developing weapons. Tulsi Gabbard testified before congress to that effect earlier this year. Given that Iran is a theocratic state and their top religious leader issued a ruling that the use of nukes violated a couple of prohibitions in the Koran (making land uninhabitable, a big no-no, and the slaughter of innocents, technically also a big no-no although it has more wiggle room) it doesn’t seem at all likely that the current Iranian regime would use nukes aggressively even if they were developing them.
These aren’t the best links because the ones I remember are either months old news articles or decades old analyses, and I didn’t have time to dig up the exact ones I wanted, but they’re both directly on point.
https://www.cia.gov/resources/csi/books-monographs/cia-support-to-policymakers-the-2007-nie-on-irans-nuclear-intentions-and-capabilities/
https://www.mid-day.com/news/world-news/article/trump-rejects-intelligence-report-says-tulsi-gabbard-wrong-on-iran-nuclear-program-23574738
Iran…and specifically the religious rulers…have been really consistent, over the long years, in maintaining that nukes are Haram(something belonging to Allah, and not to be messed with).
I suspect that they’ve quietly changed their tune due to recent events and words…and the obvious example of the still uninvaded/attacked North Korea.
Us/Zionist foreign policy(sic) has pushed the rest of the world…starting with Iran…into seeing the need for them to have such a horrific deterrent.
Moahmmar and Saddam are a couple of other glaring examples of what happens when you trust in the good will of Us/Zionazis, and their numerous poodles.so, well done, all!
USA Empire and its worst poodle(israel) cant end soon enough.
its gonna be hard, for us amurkins, of course…this loss of empire status…and my fellow countrymen will likely blame the Mexicans, etc….but the empire must end, once and for all.
perhaps a future UN-Like apparatus can include a universal ban on any weapon beyond a sword or a sling…and make duelling between leaders a thing, again.
get them idiots some skin in the game…as ive heard so often from the hillaries, etc of our own political elite, in ref to healthcare, and such.
and while we’re at it…can we please, please eat the rich?
rich folks being at risk of being food is the best deterrent from bad behaviour i can think of.
Si se Puedas!
Iran, Japan, Taiwan, South Korea, South Africa, Canada, Germany, the Netherlands and Brasil are all “nuclear threshold” states – basically one or two steps away from having The Bomb. No reason to single Iran out, me thinks. We’ll know when they announce, test or use one, the rest is just guessing.
I find it much more interesting to ponder if Israel actually has nuclear warheads, and if it does, how many. They are extremely expensive to develop, construct and maintain – and due to the radiation they degrade and have to replaced (which is expensive to the second power). Comparing Israel’s military budget to other nuclear powers they seem to be quite a lot behind and certainly can’t afford to have hundreds of warheads.
I thought we were fairly sure that Israel does have the bomb. Even the CIA-adjacent Wikipedia reports 90 to 400 warheads.
FWIW, Japan has a large stockpile of Plutonium — over 40 tonnes, apparently enough to make over 5000 nuclear weapons — and this was a policy decision made in planning their nuclear village. The Plutonium has been a byproduct of all the fission reactors and thus available in case the need arose to develop a bomb.
In view of the end of WWII, of course many in the Japanese public would be loudly against such development, though the far-right party Sanseito recently campaigned on doing exactly that.
Add in the fact that Israel is tiny size wise and population wise so even one nuclear explosion would be devastating whereas Iran is the opposite and could absorb multiple explosions.
Alastair Crooke has been talking about this with additional detail based on Postol.
Postol has drawn up the technical outline for a 174 centrifuge cascade that would require a mere 4 to 5 weeks for Iran to obtain enough weapons-grade uranium (as enriched hexafluoride gas) for one bomb.[…]
What may be even more shocking to the non-technical observer, is that Postol has further demonstrated that a 174 centrifuge cascade could be fitted within a space of a mere 60 square metres – the floor space of any modest city apartment, and would require, as power input, just a few tens of kilowatts.[…]
In another culling of the shibboleths surrounding the Iranian reality, building a spherical atomic bomb requires no more than 14 kg uranium metal 235, surrounded by a reflector. ‘It is not high tech; it’s garden shed stuff’. Just assemble the pieces; no test needed. Postol says: ‘Little Boy’ was dropped on Hiroshima.
I’m no expert but apparently the Hiroshima bomb fired such as sphere down a gun barrel into a uranium spike that completed the critical mass. This is not the most efficient use of the expensive material but can be compact enough that the gun design was used to make atomic artillery shells back in the 1950s when the US Army wanted to play with nukes too. And of course there’s the terrorist ground transportation delivery method as well.
And btw the Los Alamos scientists were not absolutely sure that the gun type would work but had the implosion bomb–tested in New Mexico–as backup.
Crooke link.
https://strategic-culture.su/news/2025/08/04/a-further-u-s-attack-on-iran-would-be-pointless-kabuki/
yeah. the spherical implosion method is difficult to get right…everything has to work perfectly, or its a dud.
this was developed because, at the time, plutonium was hard to make…hence our buildout of those kinds of reactors for domestic power.
the gun type is relatively simple…its just not “efficient”…or “elegant”.
with a couple of pounds of fissile material, and the relevant protective apparatus, i could prolly build one in my shop, if i put my mind to it…as could any number of radical DIY’ers across the world.
in fact, there was a tom clancy novel, way back(dont remember which one) that had almost a manual level of detail in the step by step that needed to be done…and that was a spherical implosion device.
gun type is easy by comparison.
fire a cannon ball of fissile material into another bunch of fissile material at great force and speed, where the latter cant get away…and there you go.
that the USSR and USA went all crazy developing such sophisticated versions of such weapons is a testament to insanity.
Fear of Communism really did a number on the minds of our elite class.
Now its fear of any competition, at all…anybody bucking our will…
“we can endure neither our vices, nor their cure”-Livy
As often, it’s about words and definitions. If Postol is right, Iran could enrich enough U235 to weapons grade to enable it to have the raw material for, say, 10 rudimentary warheads of uncertain yield, which could be carried by some existing Iranian missiles. There remains the problem of accuracy with a warhead and delivery system that have never been tested together, and where the small yield (say 10kt) means that you need to be very accurate to achieve the desired effect. (Although a hit anywhere in Israel would be very bad news, of course.) It’s also not clear to me (perhaps we have a nuclear physicist in the house) how the warhead could be detonated at exactly the right point. I’d just add that it’s almost impossible to talk sensibly about casualties: models give results that vary wildly with time of day, season of year, weather conditions, wind, degree of warning and preparation and whether the explosion is a groundburst or an airburst. As PS points out above, Iran has just elevated itself into the club of “we could if we wanted to” nations, able to move quickly to a deliverable system, unlike Israel which has had deliverable systems for decades. Politically, that means that it can maintain a posture of strategic ambiguity, which is probably the best option in the circumstances.