Assessing the ticking clock on Iran's nuclear weapon

The battle is on over when Iran could break out to a nuclear weapon, but opinions vary on what that means.

AN IRANIAN FLAG flutters in front of the International Atomic Energy Agency headquarters in Vienna last year (photo credit: REUTERS/LEONHARD FOEGER)
AN IRANIAN FLAG flutters in front of the International Atomic Energy Agency headquarters in Vienna last year
The clock is ticking.
In May 2019, November 2019 and on January 5, Iran made various jumps forward in the speed and volume of its uranium enrichment.
Its speeding up this enrichment potentially brings the moment closer when the Islamic Republic could develop a nuclear weapon and the US or Israel might consider preemptive military action.
But even on the pro-Israel side of the aisle there are vastly different opinions about how fast the clock is ticking and when the critical moment might come about.
Most importantly, there is disagreement about whether Iran will cross a key threshold for developing nuclear weapons before or after the November US presidential election.
What are the different views and how will the US and Israel decide at what point Tehran’s gradual movement toward a nuclear weapon is too close?
The debate was restarted on January 14 when IDF Chief-of-Staff Lt.-Gen. Aviv Kochavi said that Iran would not have enough enriched uranium for a bomb before the end of 2020 – or after the US presidential election.
Kochavi also said that even once Iran had enough enriched uranium that it would take its nuclear scientists another year before they could actually fire or deliver a nuclear weapon.
In Kochavi’s terms, Iranian breakout is still around two years away.
What was somewhat stunning about this statement was that such a calculation would seem to assume that Tehran has made no progress toward a nuclear bomb since May 2019.
In other words, the 2015 nuclear deal left Tehran about 12 months from a bomb and Kochavi was saying that, as of January 14, it was still about 12 months from having enough enriched uranium for a bomb.
This would seem to be a problematic assumption since the IAEA itself reported by November 2019 that Iran had increased its volume of enriched uranium and that Iran had activated 164 IR-2ms and 164 IR-4s advanced centrifuges. These centrifuges enrich uranium at a speed several times faster than the standard IR-1.
Further, a consistent line of statements from top Iranian officials since November 2019 have suggested that the Islamic Republic had already sped up enrichment even more both in December 2019 and in January.
In fact, taking Iranian officials’ statements literally, former IAEA official Olli Heinonen told The Jerusalem Post on January 7 that if Iran reattached some more advanced IR-2m centrifuges, it could potentially have enough enriched uranium for a nuclear bomb as early as April.
Now, add in that former IDF intelligence chief Amos Yadlin said Kochavi’s announcement had some inexact statements. Add in also that Yadlin said the Islamic Republic’s breakout time was probably down to six-to-eight months, and things become thoroughly confused.
Is Iran likely to breakout in April (as Heinonen says), in July-September (as Yadlin says) or in the end of 2020 (as Kochavi says)? And why do these top intelligence officials, who all have a pro-Israel leaning, disagree so drastically?
For one, the Post has learned that they are not using the same math.
Kochavi’s predictions are based on the idea that Iran would need 1300 kg. of low-enriched uranium and 40 kg. weaponized enriched uranium for a nuclear bomb.
Heinonen’s predictions are based on the idea that Iran would need only 1000 kg. of low-enriched uranium and only 25 kg. weaponized enriched uranium for a nuclear bomb.
Yadlin did not specify what number he was working off of. But it was probably the same numbers as Heinonen, with him just making more conservative estimates about how much Iran will accelerate its uranium enrichment beyond its most recent accelerations.
Put differently, Heinonen may suspect that Tehran is going to continually increase its uranium enrichment speed, whereas Yadlin may believe that its nuclear scientists have reached a plateau in increasing their speed.
THESE DIFFERENT assumptions probably stem from a different understanding of what the Islamic Republic’s current game is.
If its game is to full-court-press the West, then it would continue to speed up toward a bomb, maybe hoping to catch the West with its guard down and without time to respond or act to stop it.
What if Iran’s game is to increase the pressure on the West but to still remain a sizable distance from the finish line? This would be if it wants to avoid inciting Israel or the US into preemptive military action. In that case, Iran would soon need to level off or even quietly slow down its uranium enrichment.
That explains the April versus July-September disparity between Heinonen and Yadlin – but what about Kochavi?
The IDF does not explain its numbers. But it is a large institution and when it puts out numbers, they cannot just be dismissed. Former Israeli Atomic Energy Agency director Shaul Chorev also indicated to the Post that he generally supports Kochavi’s calculations.
At the same time, Heinonen told the Post that the 1000 kg / 25 weaponized kg numbers he was using are what the IAEA uses and has used for decades. In fact, he said that 20 kg was probably enough for a bomb and that 25 kg was a slightly conservative number.
An Institute for Science and International Security report on Iran breakout times in September 2019 referred to multiple scenarios of Iran using anywhere from 900 kg of low-enriched uranium to 1300 kg. The Union of Concerned Scientists puts the number of weaponized uranium at between 40 to 50 kg.
There is no clear answer to this disparity in the numbers, but a number of factors could explain this. The IDF may assume that some of the enriched uranium may be faulty or that Iranian centrifuges may break at a certain rate based on Iran’s generally poor record with centrifuge upkeep as compared to other countries.
There may be different assumptions about loss of material during processing or delivery of the nuclear material by warhead, and different delivery methods can require different numbers.
Finally, low-enriched uranium can mean different things – and at a 3.5% or 4.5% enrichment level, may require different quantities to get to weaponized uranium.
After all of this, the official IDF assessment by Kochavi tells us something else.
Either the IDF on its own, or on behalf of the Israeli government (sometimes the IDF and the prime minister have subtle but important disagreements on issues related to Iran), wanted to signal that Iran is not close to a bomb and probably will not be until sometime after the US election.
Moreover, the IDF chief’s headline was that Iran is two years away when you add in the time it would take it to perfect delivery or firing a nuclear missile.
In contrast, most of the discussion about Iranian breakout in pro-Israel circles relates merely to when it will have enough material for a bomb. Kochavi did not do this by mistake.
He wanted everyone who was listening to know that, from his perspective, Supreme Leader Ayatollah Ali Khamenei is still sticking with a strategic patience tactic of not trying to breakout with a nuclear weapon until after the November US election.
This means the IDF is banking on the idea Khamenei is afraid of what US President Donald Trump might do and believes it is in his interest to wait to see if a less anti-Iran president is sitting in the White House after November.
IN CONTRAST, Yadlin and some of his leading Iran-analysts at the Institute for National Security Studies have said that this is only one scenario. They say that the Islamic Republic is pushing things so close to the edge, that a sudden unpredictable escalation is very possible before November.
Kochavi may also have been signaling that he does not want to attack Iran before it gets closer to the point where it can fire a nuclear weapon and that he can live with them having enough material for a bomb.
Before the 2015 nuclear deal, Iran had enough low-enriched uranium roughly for 10 nuclear bombs. The world lived with that as long as Iran did not start weaponizing the uranium to highly enriched levels.
So should “breakout” mean enough material for a bomb (as former prime minister Ehud Barak previously maintained) or an ability to fire a nuclear missile (as former Mossad chief Tamir Pardo previously maintained)? Neither Prime Minister Benjamin Netanyahu nor Blue and White leader Benny Gantz want to show their cards on that issue.
Everyone is also still scrambling to figure out whether the US would help with a preemptive strike on Iran if Khamenei ordered a breakout toward a nuclear weapon or leave the issue to Israel. Before Trump ordered the killing of Iranian Revolutionary Guards Corps. Quds Force chief Qasem Soleimani, most of the Israeli defense establishment believed that Trump would leave it to Israel. Now there is more debate about whether Trump will use force only if a US soldier gets killed by Iran or may also use force in other scenarios.
What one comes away with is that there is a lot of hope that Khamenei will wait until at least the November election. However, when it comes to fateful national security issues regarding Iran, there are critical disagreements about what breakout means, when it might be, and yes, even about math.