When is 5 Percent Not 5 Percent?

The Iranian nuclear deal (more on the deal and the secret side agreement; see also this) refers to uranium enrichment thresholds of 5% and 20%. These may not sound too threatening, given that a nuclear weapon requires enrichment to around the 90% level. BUT the percentage enrichment of the uranium is NOT a good indicator of the amount of work required to get there.

Start with a tonne (2204 pounds) of natural uranium feed–to enrich it to 5% will require about 900 Separative Work Units–SWUs being an indicator of the amount of energy, time, and capital equipment required for the process. Take to 5% enriched product and continue enriching it to 20%, and the incremental cost will be only about 200 SWUs, for an accumulated total cost of 1100 SWUs. And if you want to turn the 20% enriched substance into weapons-grade 90%-enriched uranium, you need add only about another 200 SWUs of effort, for a grand total of 1300 SWUs. Thus, the effort required to get to that seemingly-harmless 5% threshold is already 69% of the way to weapons grade, and 20% enrichment is 84% of the way there. See this article, which explains that “the curve flattens out so much because the mass of material being enriched progressively diminishes to these amounts, from the original one tonne, so requires less effort relative to what has already been applied to progress a lot further in percentage enrichment.”

There has been very, very little media coverage on this point. One place the issue was discussed was in February and September 2012 reports by the American Enterprise Institute, which were discussed and excerpted at PowerLine in November 2013. Note that the AEI analysis shows an even flatter enrichment curve than the one in the article I linked above–AEI is showing 90% of the total effort for weapons-grade as being required to get to 5% enrichment, rather than “only” 69%. In either case, it should be clear that possession of large quantities of material enriched to 5% is a very nontrivial milestone on the way to constructing a nuclear weapon.

Meanwhile, 4 billion dollars worth of frozen Iranian funds are being unfrozen and sent to Iran. Money is fungible, and almost certainly some of this money will go to support Iranian-backed terrorism, funding operations intended to kill American military personnel, Israeli civilians, and quite possibly American civilians in this country as well. And some of it will probably go to support R&D on advanced centrifuge technology, allowing Iran to move even more quickly to a nuclear weapon when it decides to do so.


There is activity in the U.S. Congress toward passing legislation that would require stronger sanctions against Iran, probably with a deferral for 6 months of longer contingent on Iran meeting specified milestones in dismantling its nuclear weapons program. Obama has indicated his intent to veto any such bill, and it is not clear if there would be sufficient votes to override the veto…and Obama’s White House, it seems, is “unsettled” by Jewish lobbying in support of sanctions legislation. A cartoon published by The Economist magazine shows Obama being shackled by the seal of the U.S. Congress..covered by Stars of David…reaching out to shake the hand of Iranian President Hassan Rouhani, who is followed by extremists burning an American flag. The cartoon seems to indicate that Congress is run by Jews or Israel and to suggest that those who favor stronger sanctions are morally equivalent to Iranian extremists (as well as implying that Rouhani is not himself an extremist or a tool of extremists.) I’d say it’s pretty clear that the cartoon, which has since been withdrawn from The Economist’s website, is openly and explicitly anti-Semitic, as well as objectively pro-Iranian-regime, in the same sense that Orwell referred to the activities of certain Brits as being “objectively pro-Fascist.”

In any event, it’s ridiculous to think that only Jews and/or supporters of Israel should be concerned about Iranian nuclear weapons. An Iranian weapon capable of being delivered by a ballistic missile would have a very serious political impact, domestic as well as foreign-foreign-policy-related, in all countries within the range of those missiles, which would increase over time as with additional missile-development programs. Iranian missile basing in Latin American countries whose regimes are hostile to the US (Venezuela, for example) seems possible; also, missile threat to the US by surface ship and/or submarine, and the supply of nuclear weapons to terrorist groups and other rogue regimes.

It should be obvious that the people who are supposed to be driving America’s response to this deadly threat–Barack Obama and John Kerry–are not up to the job.

11 thoughts on “When is 5 Percent Not 5 Percent?”

  1. This is an interesting side light on the Manhattan Project and the story of the Navy contribution, which had found another way to enrich feedstock for the Y12 program.

    Oppenheimer informed Groves that Philip Abelson’s experiments on thermal diffusion at the Philadelphia Naval Yard deserved a closer look. Abelson was building a plant to produce enriched uranium to be completed in early July. It might be possible, Oppenheimer thought, to help Abelson complete and expand his plant and use its slightly enriched product as feed for Y-12 until problems with K-25 could be resolved.

    This story is related in fiction by Herman Wouk in his great novels, Winds of War, and War and Remembrance, in which this story is told. No doubt the 5% solution was part of the process to get to the level of enrichment to be allowed the Iranians.

    Marie Curie processed a “mountain” of Uranium ore left over from Bohemian glass factories to extract a gram of Radium.

  2. I forget where I saw it first but one thing that has stuck with me is the idea that Iran is not pursuing a nuclear weapon at present, instead they are pursuing “breakout capability”. Meaning, they don’t necessarily want to have a nuclear weapon on the shelf right now, but they do want to have the capability to be able to produce a nuclear weapon within, say, a 3-6 month window any time they want. And that’s why allowing enrichment to 5% or 20% is so dangerous. It only took a matter of months for the US in WWII to design and build novel enrichment facilities from scratch and process natural Uranium (0.7% enrichment) into enough HEU to make an extremely inefficient bomb.

    If the Iranians have been developing implosion bomb technology, and there is every reason to believe they have, then they would need about 1/10th as much HEU as is required for a gun assembly bomb. And if they already have huge stockpiles of 5% enrichment Uranium sitting around then it would only take a few passes through their ALREADY EXISTING Uranium enrichment facilities to be able to have not just enough HEU for one bomb, but for many bombs. If they already have all of the other components for the bombs other than the “physics packages” sitting around, and there’s very little reason to imagine they wouldn’t, then they could proceed along their breakout capability path in a very short period. Not just a matter of months but perhaps a matter of weeks even.

    There’s really no way to impose inspections or to detect from afar the development of the non-nuclear aspects of nuclear weapons technology. Refining Uranium or producing Plutonium requires lots of infrastructure and lots of power, it’s difficult to hide. Developing explosive lenses has an incredibly small footprint. And even testing full-scale nuclear bomb designs without the nuclear material is something that the Iranians could be doing right now every single day without anyone noticing. The facilities needed for R&D could be nothing more than offices, since most of the work is on paper, and the testing would just be very small scale explosions which could happen anywhere in their vast country, including in underground facilities.

    In effect, the Iranians are developing nuclear weapons under everyone’s noses, with the tacit approval of the world powers. It’s unbelievable, and hopefully it will go down in history as a cause of everlasting shame for this administration.

  3. Robin…yes, it seems quite possible that their intent is to develop a real option, to use the term borrowed from finance, for a nuclear weapon. With the components almost ready to go, they could bide their time and then finish, assemble, and test the weapon when either the US is otherwise heavily distracted, or some crisis faces the Iranian regime.

  4. I’m not seeing the direct comparison, but maybe I’m missing something. An example of a real option would be if legislation had been passed and rules & environmental approvals pre-established such that IF the trigger were to be pulled on a physical infrastructure campaign, everything would be ready to go rather than requiring a year or three of paperwork before the first shovel could be turned.

  5. One good example of a Real Option would be Amazon’s build-out of a warehouse and IT structure which *allowed* them to expand into any of a wide range of markets whenever they thought the time was right for entry into a particular market.

  6. Obama and Kerry have just given the Iranians the funds they need to build a dirty bomb that can be used against Israel and the US – 2 places with lots of jews. A dirty bomb can make these places radioactive for many years.

    It can be delivered to Israel strapped to the back of a camel. To any US city in the next heroin shipment from Afganistan.

  7. ” To any US city in the next heroin shipment from Afghanistan.”

    I am very concerned about this. We, after all, are the “Great Satan.” The left doesn’t understand fanaticism. Nothing means much to them, even if they are smart enough (just barely), to see that Muslims can’t be trifled with, like Catholics and Jews.

  8. From the American Thinker: “The Obama administration is angry that Senate proponents of additional sanctions against Iran (to be instituted if the interim accord expires without a final agreement) appear to be more skeptical of Iranian promises than the president and Secretary Kerry are. The administration is angry as well that signers, particularly Democratic senators, of the Kirk-Menendez Amendment find themselves in accord with the security concerns of the government of Israel. And finally, the administration is angry with American Jews.”


    “The LA Times earlier this week quoted Salehi of Iran’s nuclear agency, saying on state television, “The iceberg of sanctions is melting while our centrifuges are still working.”

    Read the whole thing.

  9. Karin McQuillan: “I called a hardheaded realist, a Harvard trained PhD who has been watching the Middle East professionally for decades, to ask him about Obama’s Iran deal. This is what he told me.

    It’s done. Iran will get a bomb.”


    “This deal makes it essentially impossible for Israel to strike — not least because the U.S. has Israel under a microscope, by satellite and other technical means, and also with spies in the government and the IDF (Israeli Defense Force). At the first hint that a mission is imminent, the White House will leak it to the Washington Post, the New York Times, destroying operational security. Just as the U.S. leaked about Israel’s strikes into Syria.

    If despite this Israel tries to strike, they are the ones who will be viewed as pariahs and warmongers. They could face economic sanctions. Obviously Bibi didn’t trust Obama, but Obama managed to betray him and Israel anyhow.”


    “The only real answer is regime change. Obama doesn’t want regime change. Remember, when the protesters were in the streets of Cairo, we forced our ally Mubarak to resign, with brutal public and private pressure. But when the protesters were in the streets of Tehran, and the regime’s thugs were attacking and murdering them, Obama did nothing. He could have used the occasion to tighten sanctions even more, and using the pretext of human rights he could have had European public opinion on his side.

    “Obama wants the Iranian regime to survive, he wants to negotiate with it, and he wants to ally with it. What a coup that would be for Mr. Obama — he would get a second Nobel.

    He is like the community organizer who goes into a rough neighborhood and wants to reach an agreement with the strongest street gang, so they will let him organize in peace. That’s what Obama is doing, by bending to the Iranian demands and negotiating with Hezb’allah.”

    Read the whole thing.

  10. Oh yes, we will have a nuclear Iran. As for Israeli high tech industries moving here, I doubt it. First, the Democrats want illiterate Mexicans, not highly intelligent Jews. Especially Jews with experience with Islam.

    Cheney begged Bush to strike the Syrian nuclear facility. It was one of several sources of tension between them in the second term.

    Can the Iranian technocrats restrain the crazies among the mullahs and stop them from attacking Israel ? I don’t know. There is that suicide strain in Islam, especially Shia Islam. A good book about the world of Islam and Iran is The Persian Night by Taheri.

    I think we may see a war in the middle east in the next decade. Either that or an Iranian revolution. Only 2% of the Iranian population goes to the mosque.

    Our only real role in this is to “Drill, Baby, Drill.”

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