Short Answer: They may already have one.
According to the IAEA report of November 2011 (PDF), Iran has researched, developed, and most probably built all of the components needed for an implosion-type uranium bomb. The only component still lacking is a sufficient quantity of weapons grade uranium: U-235 enriched to 90% or better. Israeli Prime Minister Benjamin Netanyahu made this same point in his U.N. speech on 27 Sept 2012:
For a country like Iran, it takes many, many years to enrich uranium for a bomb. That requires thousands of centrifuges spinning in tandem in very big industrial plants. Those Iranian plants are visible and they’re still vulnerable.
In contrast, Iran could produce the nuclear detonator – the fuse – in a lot less time, maybe under a year, maybe only a few months.
The detonator can be made in a small workshop the size of a classroom. It may be very difficult to find and target that workshop, especially in Iran. That’s a country that’s bigger than France, Germany, Italy and Britain combined.
The same is true for the small facility in which they could assemble a warhead or a nuclear device that could be placed in a container ship. Chances are you won’t find that facility either. (Full Transcript)
For Iran, the only real obstacle to making nuclear bombs is having enough Weapon-Grade Uranium (90% U-235). Once they have enough WGU, they can assemble working nuclear bombs rather quickly. If they have all of the other components ready, it might take them less than a month to build a nuclear bomb. They could assemble this bomb almost anywhere, even in a “small workshop the size of a classroom”. They could place the bomb in a container ship and send it to New York City harbor. Once they have enough WGU, there is essentially no effective way to stop them from building and using a nuclear bomb.
How Soon for WGU?
The ISIS report of 15 June 2012 (PDF) assesses the time it would take Iran for a nuclear breakout, meaning an attempt to make WGU from 20% uranium. As long as Iran only enriches to 20% (technically, 19.75%), they can claim that it is for peaceful purposes. A breakout means that they start enriching uranium to 90%, which can only be used for a nuclear weapon. That ISIS report considers various breakout scenarios and the length of time needed to make 25 kilograms of WGU. The shortest possible time, using all of their available centrifuges, is 0.7 to 1.0 months. A more likely estimate of the time needed is 2 to 3 months.
Benjamin Netanyahu alluded to this ISIS analysis in his U.N. speech, when he characterized the length of time that Iran would need to make enough 90% uranium from a sufficient stock of 20% uranium in this way: “From there, it’s only a few months, possibly a few weeks before they get enough enriched uranium for the first bomb.”
But the ISIS analysis is based on 25 kilograms of WGU for each bomb.
A nuclear weapon typically requires 15-25 kilograms of weapon-grade uranium metal plus a few kilograms to account for losses during weapon component manufacturing, resulting in a requirement of 20-30 kilograms per weapon. For this report, a midpoint of 25 kilograms of weapon-grade uranium metal per weapon is selected. As discussed above, 225 kilograms of 19.75 percent LEU is sufficient, if further enriched, to produce 25 kilograms of weapon-grade uranium metal. (15 June 2012 ISIS report, p. 7.)
However, some experts state that Iran could make a working nuclear bomb (implosion-type) with as little as 7 kilograms of WGU metal:
This assessment assumes that Iran would use 16 kg of weapon-grade uranium (~90 percent U-235) in the finished core of each nuclear weapon. Sixteen kilograms are assumed to be sufficient for an implosion bomb. This was the amount called for in the implosion device Saddam Hussein was trying to perfect in the 1980’s, and the design for such a device has circulated on the nuclear black market, to which Iran has had access. Some experts believe that Iran could use less material, assuming Iran would accept a lower yield for each weapon. According to these experts, Iran could use as few as seven kilograms of this material if Iran’s weapon developers possessed a “medium” level of skill, and if Iran were satisfied with an explosive yield slightly less than that of the bomb dropped on Hiroshima, Japan. (IranWatch.org, “Iran’s Nuclear Timetable”, updated 6 Sept 2012)
According to the source cited by the above document — Thomas B. Cochran and Christopher E. Paine, “The Amount of Plutonium and Highly Enriched Uranium Needed for Pure Fission Nuclear Weapons,” (Washington, DC: Natural Resources Defense Council, revised April 13, 1995) — 7 kg of WGU would give a 10 kiloton explosion, and 9 would give a 20 kiloton explosion, with a medium level of technical expertise. With a low level of expertise, 16 kg of WGU would be needed for a 20 kiloton explosion, and 13 kg of WGU for a 10 kiloton explosion.
|How Much Weapon-Grade Uranium does Iran need?|
|Weapon Yield||Level of Technical Expertise|
|1 kt yield||8 kilograms||4 kilograms||2.5 kilograms|
|5 kt yield||11 kilograms||6 kilograms||3.5 kilograms|
|10 kt yield||13 kilograms||7 kilograms||4 kilograms|
|20 kt yield||16 kilograms||9 kilograms||5 kilograms|
|Values rounded to nearest 0.5 kilograms|
Sources: IranWatch.org, “Iran’s Nuclear Timetable“, updated 6 Sept 2012.
and: Thomas B. Cochran and Christopher E. Paine, “The Amount of Plutonium and Highly Enriched Uranium Needed for Pure Fission Nuclear Weapons,” (Washington, DC: Natural Resources Defense Council, revised April 13, 1995)
The result of the above considerations is that the 25 kg of WGU used by the ISIS report may be an overestimation. Iran is much more likely to choose to make several small nuclear bombs, than one larger bomb, for the following reasons. They are under pressure from the possibility of a conventional military strike on their uranium purification facilities at some time in the coming months. If they build only one nuclear bomb, its use would make them instantly no longer a nuclear power. But if they build two or more nukes, they can use one, and perhaps prevent a military attack on their nation by threatening the use of the other bomb(s). For Iran, the number of nuclear bombs is much more important than their yield.
As for their level of expertise, the current year is 2012, not 1982. The implosion bomb sought by Iraq in the 1980’s required 16 kg of WGU, due to a low level of expertise. But Iran has obtained more recent expertise from Pakistan and China, spent billions of dollars, and done their own advanced research (according to the IAEA report). Their level of expertise is more likely medium, not low.
Given these considerations, Iran could make three 10-kiloton nuclear bombs from 25 kilograms of WGU — 7 kg per bomb, with 4 kg to account for “losses during weapon component manufacturing”, as ISIS says. Three nukes would be sufficient for Iran’s despotic and terroristic purposes. They could use one nuke, and hold two in reserve, in different locations, such as in a city near a hospital and mosque, or in some remote location. They could nuke the U.S. (NYC most likely) and then have one nuke to threaten Israel and another to threaten another attack on the U.S.
How Soon for 25 kg WGU?
The ISIS report (15 June 2012) states that 225 kg of 20% enriched uranium hexafluoride is sufficient to make 25 kg of 90% WGU metal. The same report projects that Iran may reach the 225 kg level by November 2012 (Figure 4, p. 12).
If so, then from that point in time, a few weeks to a few months would be needed to make the WGU, and perhaps another few weeks to assemble the completed bomb(s). This analysis would seem to place the completion of 1 to 3 nuclear bombs in spring of 2013 at the earliest. Prime Minister Netanyahu alluded to this point also, when he said that Iran could have a nuclear bomb as early as spring of next year (2013).
However, there are a few problems with this estimation.
“Combined with its production at the PFEP at Natanz, Iran has produced approximately 189.4 kg of 19.75 percent uranium.” (ISIS report 30 Aug 2012)
But the same report notes the Iranian claim that it has blended down, converted, or otherwise made unusable, 96.3 kg of 20% uranium. This claim is very difficult to believe. If Iran is working toward making a nuclear bomb, every kg of 20% U-235 is precious. They have spent billions of dollars and many years, and they have endured harsh sanctions and the constant threat of a military strike, in order to make 20% uranium. Therefore, it is highly likely that this amount of 96.3 kg of 20% uranium has been diverted. In other words, Iran has deceived the IAEA, and that material is still destined for the making of a nuclear bomb.
If 225 kg of 20% uranium hexafluoride is needed to make 25 kg of 90% WGU metal, then the ratio is 9 to 1. Therefore, 96.3 kg of 20% uranium is enough to make 10.7 kg of WGU. Assuming a few kg of losses in manufacturing (as the ISIS report suggests), the 96.3 kg of 20% uranium is enough for one nuclear bomb using about 7 kg of WGU and having an explosive yield of about 10-kilotons.
If Iran is deceiving the IAEA inspectors, they could still possess that 96.3 kg of 20% uranium in gas form, awaiting a breakout. Or worse: Iran could have diverted that material to a third covert uranium purification facility, built for the purpose of making WGU in secret. In other words, Iran may have already begun a nuclear breakout.
Deceiving IAEA inspectors is not such a difficult task for a government like that of Iran. Recall that its neighbor, Iraq, skimmed billions of dollars from the U.N. oil for food program, before they were discovered. Iran could be producing more 20% uranium than the IAEA realizes. And they may have diverted the 96.3 kg of 20% uranium to a third covert purification facility, for purification into WGU.
Does Iran have a third covert facility?
The facility at Qom, which was discovered by Western intelligence agencies and subsequently disclosed to the world in 2009, was initially built covertly. Only after its completion was its existence discovered. Israeli Prime Minister Benjamin Netanyahu made this assertion in his U.N. speech on 27 Sept 2012:
Some who claim that even if Iran completes the enrichment process, even if it crosses that red line that I just drew, our intelligence agencies will know when and where Iran will make the fuse, assemble the bomb, and prepare the warhead.
Look, no one appreciates our intelligence agencies more than the Prime Minister of Israel. All these leading intelligence agencies are superb, including ours. They’ve foiled many attacks. They’ve saved many lives.
But they are not foolproof.
For over two years, our intelligence agencies didn’t know that Iran was building a huge nuclear enrichment plant under a mountain. (Full Transcript)
Iran could have a third covert uranium purification facility, solely for the purpose of purifying 20% uranium into 90% WGU. And the West might not find out about that facility until it is too late.
David Albright, an expert on Iran’s nuclear enrichment program, has repeatedly warned about this possibility of a third covert purification facility (in addition to the two at Qom and Natanz).
Amplifying worries about Iran’s nuclear intentions, in September 2009, the United States, France and Britain revealed the existence of a small, covert uranium enrichment plant being built in Iran near the city of Qom. The United States suspected the facility could be used to quickly produce enough nuclear explosive material, or highly enriched uranium, for a nuclear weapon, in what is commonly called, “break out.” The IAEA does not have confidence Iran is not building additional clandestine enrichment sites. (The Iran Primer, “Iran’s Nuclear Program,” David Albright and Andrea Stricker)
In a more recent article, Albright addressed this concern again:
Is Iran building a third gas centrifuge enrichment plant? This question has been on the minds of Iran watchers in governments around the world since former Iranian nuclear chief Ali Akbar Salehi claimed on August 16, 2010 that “studies for the location of 10 other uranium enrichment facilities” had ended, and that “the construction of one of these facilities will begin by the end of the (current Iranian) year (March 2011) or start of the next year.”
ISIS has assessed that international concern over Iran’s ability to breakout in secret should increase in 2013 due to the possible construction of a hidden centrifuge enrichment site and simultaneously growing stocks of 3.5 and 19.75 percent low enriched uranium that would allow the speedier production of weapon-grade uranium. (Is Iran Building a Third Enrichment Plant?, by David Albright and Andrea Stricker, June 4, 2012)
A third facility would give Iran a very significant advantage in its attempt to make WGU. Without a covert third facility, Iran cannot break out and begin to purify 90% uranium without kicking IAEA inspectors out of the nation and refusing all IAEA oversight of its two known facilities. This would constitute a clear signal of the start of a breakout, giving Israel and the U.S. weeks or months to respond with military action before Iran could complete a nuclear bomb. If a military strike destroys those two facilities before the completion of the breakout, Iran’s nuclear program would essentially end in failure. Therefore, a public breakout is not a viable option for Iran.
Iran has been working toward making a nuclear bomb for many years, at a cost of billions of dollars. They originally built the facility at Qom, under hundreds of feet of solid rock, on the side of a mountain, as a covert facility. They wanted a covert facility for uranium purification. Essentially, the Qom facility (near Qom, at Fordo) was built specifically for a nuclear breakout. It is protected from air strikes by its location underground, and it was originally covert. Therefore, once Fordo was discovered, the Iranian regime must have wanted to build a third facility, one that would remain covert. Perhaps they in fact have built such a facility, learning from their previous mistake at Qom and succeeding in keeping the third facility a secret. I believe that this possibility is highly likely, because a non-covert breakout would certainly fail, due to a military strike.
Where are the centrifuges?
But in order to set up a third covert facility, Iran needs thousands of centrifuges. It would be difficult for Iran to build or procure such a large number of centrifuges, without raising suspicions. Are there thousands of gas centrifuges missing or unaccounted for? Yes.
Since early 2012, Iran has claimed the addition of thousands of new centrifuges to its purification facilities.
In early 2012, Iran placed an additional 6,177 empty IR-1 centrifuge casings at the FEP [Fuel Enrichment Plant] into two separate enrichment units. Bolting the casings to the floor is typically followed by the insertion of the centrifuge rotor assembly, which is loaded from the top of the casing. Thus, Iran may have sought to imply that it intended to rapidly install these centrifuge assemblies. As of August 21, 2012, however, only one cascade, for a total of 174 centrifuges, and another cascade with 93 IR-1 centrifuges had been installed in these two units. This means that only 4.3 percent of these installed casings have centrifuge rotors in them. (ISIS report 30 Aug 2012).
But only the centrifuge casings have been installed. These casings are the least expensive, easiest to manufacture, and most available component in the centrifuge cascades. Iran could easily make thousands more casings for a third facility, without detection. Over 95% of these six thousand casings are empty, and they have remained empty for months. Where are the centrifuges?
I suggest the likelihood that Iran has already installed these centrifuges in a third covert facility. These centrifuges may have been working on purifying the 96.3 kilograms of 20% uranium that Iran claims was down-blended or otherwise converted into unusable form. The ISIS report of 15 June 2012 estimates that, if all 16 cascades at Fordo (Qom) were used to purify 20% uranium into 90% WGU, it would take those centrifuges (totaling nearly 2800) about 1.5 months. If the number of centrifuges were only 2100, the time required would be about 2.0 months (ISIS Report 15 June 2012, p. 8). If only 2100 to 2800 of the 5900 unaccounted for centrifuges are installed in a third facility, Iran can purify 25 kg of WGU from 225 kg of 20% uranium gas in 1.5 to 2.0 months.
The 96.3 kg of 20% uranium was reported as blended down or converted several months ago. By now, that amount of 20% uranium — if a third covert facility exists and is operational — may already have been converted to 90% WGU gas, or even to the metal form needed for a bomb. So it is possible that Iran will have a working nuclear bomb before the end of 2012. They may have one bomb already.
By November 2012, Iran will have produced about 225 kg of 20% uranium (including the 96.3 kg), which is enough for three small nuclear bombs. A covert facility with 2800 centrifuges would need only about one month to convert the remainder of the 225 kg (225 – 96.3 = 128.7) into WGU and about another month to make the bombs.
Signs to Watch for
If Iran has a third covert uranium purification facility, they will need to somehow transfer the 20% uranium from the other two facilities. So if they again claim that some amount of 20% uranium has been made unusable, another 90 to 100 kg or so, that would indicate that they are making enough WGU for a second bomb.
Another indicator that Iran might be close to completion of nuclear bombs would be if Iran stops producing 3.5% uranium, and tasks all of the centrifuges at Qom and Natanz to making 20% uranium.
What would be even more worrying, is if Iran claims that they are closing one or both of their nuclear facilities (Qom and Natanz). If they claim to be ending their nuclear program, and therefore also claim that IAEA oversight of the current stock of 20% uranium is no longer necessary, they could transfer all of the 20% uranium to the covert facility. It would then take them only a couple of months to make a couple of nukes.
There are a number of possible conclusions to Iran’s attempt to obtain nuclear weapons. I think the most likely is that Iran obtains two or three nuclear bombs (but publicly claims to have more), and then uses one, all prior to any military strike by Israel or the U.S. Such an attack by Iran against Israel or the U.S. would be the start of a world war. The Muslim nations broke out in violent protests over a conflict about a movie (really, just a YouTube video). If there is a military conflict between Iran, on the one side, and the U.S. and Israel on the other side, the Arab/Muslim nations of the Middle East and northern Africa will all take the side of Iran. The European nations will side with the U.S. And that is essentially how World War 3 starts.