Analysis // Iran nuclear agreementThe basis for a permanent deal: deep, verifiable changes to Iran’s nuclear program

Published 23 January 2014

A new study says that only broad and verifiable changes to Iran’s current nuclear program could serve as a basis for a permanent nuclear deal between Iran and the international community. Among the changes: reducing the number of Iran’s uranium-enrichment centrifuges from the current 19,500 to no more than 4,000, and limiting Iran to one enrichment site; converting the heavy-water reactor being built in Araq to a light-water reactor fueled by low-enriched uranium; and imposing a tight, intrusive inspection regime for at least twenty years.

The interim nuclear agreement between the P5+1 and Iran entered into effect on Monday, and its 6-month duration would be used for intense negotiations over a permanent agreement.

The purpose of the permanent agreement is to reassure the world that Iran will not build nuclear weapons and will not become a nuclear threshold state. A nuclear threshold state is a country which has all the components for nuclear weapons – fissile material, warhead design, and delivery vehicles – and the means to produce them. A nuclear threshold state – Japan is a good example – can assemble these components into an operational nuclear weapon on a short notice if the leaders of the country so decide.

The time between the decision by the country’s leadership to go nuclear and having the bomb available is called “breakout” time. A country like Iran would want the breakout time to be as short as possible, so if the country’s leadership decided to build a nuclear weapon, the United States and Israel would not have enough time to prevent it by attacking Iran.

Scientists and nuclear experts agree that before the interim agreement went in effect on Monday, Iran’s breakout time for a crude nuclear device was about thirty days. Intelligence services know how much uranium enriched to 20 percent Iran had (nearly 200 kg), and they know the number of Iranian adanced centrifuges capable of enriching that uranium to weapon-grade 90 percent (1,200), so even a college physics major could calculate the number of days it would have taken Iran to enrich its 200 kg of 20 percent uranium to weapon-grade quality, and how many Hiroshima-size bombs Iran could have produced.

What Iran could build in thirty days, however, was a Los Alamos-like device that can be placed on a tower or inside a well and detonated (that is, if Iran has already mastered the triggering sequence). Iran is about a year away from building an operational warhead, because the miniaturization and machining processes required, and building a reliable triggering mechanism for the warhead – if Iran does not yet have one — are demanding tasks.