Iran already has nuclear weapons capability

[shaayecanaan]

an interesting post from Jeffrey Lewis. He goes through the sums and concludes that Iran already has enough MEU to yield sufficient weapons-grade uranium for a single, viable nuclear device (albeit only a moderately-sized one). However, the Iranians have obviously chosen not to make such a device.

A good post and well worth a read:-

http://lewis.armscontrolwonk.com/archive/5699/how-close-is-iran-to-bomb-1

Excerpt:

But to make a long story short, Cochran and Paine estimate that a relatively low-tech bomb program would need between 8 and 16 kg of U-235 for a pure fission weapon (an “A-bomb”), depending on how much explosive yield is desired. A medium-tech program, which is perhaps where Iran fits thanks in part to the foreign assistance described in GOV/2011/65, would need between 4 and 9 kg of U-235.

As a reminder, Iran already has about 11 kg of U-235 in the almost-20% U-235 UF6 that’s sitting in storage, and about 20 kg of U-235 available if you throw in other material that could be turned back into UF6. What’s more, GOV/2012/37, the source of the UF6 numbers above, is already out of date. As Table 3 of the report shows, more UF6 enriched to almost 20% U-235 is accumulating rapidly.

The bottom line is that Iran probably has enough material on hand today to support the breakout scenario that Israeli officials reportedly fear is coming within months.

On to the next artificial threshold of capability!

[Hydra]

1. So, if I'm reading that right, they currently have enough for 1-2 weapons

Of course, if they really wanted a weapon, they could just ask Russia or China for a few. Besides the fact that the NIE says they're not going for one.

...but why let facts deter a good war? Iraq worked out so well for us, didn't it?

[shaayecanaan]

2. I think its become clear that they don't want a nuclear weapon

but they want to be a threshold nuclear power (which is essentially the same position taken by Australia, Japan, Germany, and many other states).

The Australian Government, for example, has a nuclear facility at Lucas Heights. This facility enriches uranium. The excuse given for this is that the enriched material is for medical isotopes (which is exactly the same excuse given by Iran, and many other states). In reality medical isotopes can be obtained from third parties at a substantially lower cost.

The reality is that Australia does not want to produce nuclear weapons, but wants to be able to create them at pinch if it ever needs to. Potentially, a nuclear warhead could be loaded onto one of the anti-ship missiles that Australia's submarines currently carry. Its not ideal, but as a deterrent it would do the job.

Technically, its a lot easier to enrich uranium from 20% to 80-90% than it is to get to that initial 20% mark, particularly if you have a lot of uranium enriched to 20% and can afford to lose a bit in getting there. A timing device for an enriched uranium bomb can be extremely simple (as in the Hiroshima bomb) - so simple that you don't need to test it for it to be an effective deterrent.

By world standards, its not particularly formidable. Its still doubtful whether Iran's missiles could even reliably hit Israel. But they don't need to be certain. They just need enough of a deterrent to head off an invasion.

There are a number of interesting responses to the OP, but this one is worth reading in particular:-

The historic track record is that everyone who ever attempted to build a basic fission weapon got it pretty much right the first time, with the exception of North Korea and possibly Pakistan. So, even without all-up testing, Iran could be ~75% confident of full design yield and ~90% confident of at least high sub-kiloton yield with the first combat use of a hypothesized breakout nuclear weapons system.

100% reliability, that definitely requires testing, in the sense of actual nuclear explosions. Even if someone were to sell the Iranians the complete design drawings and manufacturing instructions for a tested nuclear weapon, they wouldn’t be able to get above 99% confidence without a test.

And perhaps most importantly, an awful lot of what are referred to as nuclear “tests” are not really tests at all, but demonstrations. If the goal is deterrence, or for that matter intimidation, it doesn’t matter how reliable your bombs actually are or how confident you are in their design; what matters is how confident your enemy is that your bombs will work. So, even with a 100.00% reliable weapon, the Iranians may need to set one off to accomplish their goals.

Whether a bomb that the Iranians know to be 75-90% reliable and the rest of the world can only guess at, will serve Iran’s needs, is for Iran to decide. Israel has maintained an effective deterrent with such weapons for thirty or forty years, but Iran may have different requirements.

[azurnoir]

3. well those claims could serve someone needs not necessarily the US's or the rest of the world's

but someones

[azurnoir]

4. If that is the case then Bibi's bomb my well be set to go off

that along with the drone that Israel claims is of Iranian origins being shot down yesterday and hey its only the first week of October

[shaayecanaan]

5. If Israel attacked Iran

then I expect Iran will say it cannot comply with IAEA inspections - and I imagine the IAEA will say that they cannot conduct inspections with the threat of bombs falling around their heads.

As I understand it, the cameras that monitor Iran's facilities are attended to every six weeks or so by the IAEA - the recordings are not transmitted to them live but are contained within the recording devices themselves. Accordingly, if the recordings are not collected then the weapons inspectors are in the dark. Potentially, Iran could then take all of its MEU and convey it to its deep underground facilities where it could be enriched to weapons grade, potentially quite quickly, without anyone necessarily knowing.

[bemildred]

6. This grovelling over technical minutae is pointless.

It is quite clear that the Iranians can make a bomb, all by themselves, no yellow cake, no nothin' from outside, if they so choose. Been there for some time. If they wanted one, they would have one.

[shaayecanaan]

7. Exactly. Almost every state is "nuclear weapons capable"

its not a particularly large technical challenge to enrich uranium if you're prepared to take the time to do it. Even North Korea, a tinpot state in every sense of the word, was able to build a bomb. Its not whether a state is capable of building a bomb, they mostly are, but whether they choose to.

I was on a plane the other day and they had Robert McNamara's "Fog of War" documentary playing on the IFE. He made the remark that non-proliferation is a political challenge and not a technical one. You prevent states from building nuclear weapons by giving them a political reason for not doing it.

In the Cold War, the political reason was that the countries could comfortably reside under the nuclear umbrella afforded them by either the Soviet Union or the United States. Apart from the three occasions in which either the US or the Soviet Union nearly provoked Armageddon, it worked quite well.

Iran has no such foreign benefactor. I don't know if the US has made any serious proposals to Iran, but I think to get a deal there would need to be a security guarantee for the United States.

[bemildred]

8. We'd be high-pressure selling it to them with a different government, with kickbacks all around.

I don't follow the many proposals and counterproposals, but my general impression when I have dipped into them has been that Iranian demands to get something substantial in return: end of sanctions, normalization, etc., if they comply with our demands, is the "stumbling block" to resolving the crisis, but I consider that a pretext, since the fact is nobody really wants to resolve the crisis, everybody finds it quite convenient.

[sabbat hunter]

9. making a nuclear weapon

is more than having the fissible material. And then making one small enough to fit on a missile is another task entirely.

[bemildred]

10. Yep, I've heard the stuff is tricky to handle too. nt

[shaayecanaan]

11. Making a bomb with weapons grade uranium is a piece of cake

The Hiroshima bomb was as simple as they go: a rack with two halves of the core on each end, and two TNT charges to slam the two halves of the core together.

It was inefficient as hell, but it did the job. Now, such a simple rack-type bomb would be bulky, but there are plenty of timing devices that the Iranians could go with that wouldn't stretch them technically and which they could fit in their medium range ballistic missiles. Basically, if you have the capability to make the missiles, you have the capability to make the warhead.

True, the devices they could come up with in the near future would be in the range of kilotons rather than megatons, but probably good enough for deterrence purposes.

This is why you go with uranium rather than plutonium or even a hydrogen bomb (which requires a fissile bomb as part of its timing device anyway). Its a lot harder to create weapons grade uranium than simply go with plutonium but much easier to work with once you have it.