Truman National Security Project

Timetable to an Iranian Bomb — How long does the world have?


Benjamin Netanyahu, the Prime Minister of Israel, made a newsworthy declaration to the American public last week.   In his words, Iran is “six months away from being about 90 percent of having the enriched uranium for an atom bomb.” Media reports widely interpreted this to mean that the Israeli leader judges Iran is half-a-year from having most of the enriched material to fuel a nuclear weapon.  Others deciphered it to mean Iran could have an actual bomb by that time.

Neither is accurate.

What the Prime Minister said was not controversial, or new.  The former chief United Nations inspector of Iran’s nuclear program, Olli Heinonen, wrote last April, “If the aim is to produce 90% enriched uranium [i.e. highly enriched uranium], reaching the 3.5% level requires some 75% of the work. By the time 20% enrichment is reached…90% of the work has been done.”  According to Netanyahu, it will take Iran six months to have enough 20% enriched uranium, which, if further enriched, could rapidly be turned into weapons grade material for a single bomb.

In what was likely not a coincidence in timing, Netanyahu’s statement came almost one week after Leon Panetta, the U.S. Secretary of Defense, said the U.S. has “little more than a year” to respond to Iran if it made a decision to acquire a bomb.

Both Netanyahu and Panetta’s statements are correct, entirely compatible, and support the Obama Administrations position that we have time to allow diplomacy to work.

Netanyahu estimates Iran will have a bombs-worth of 20% enriched uranium by March. Iran would then need to feed this material into its spinning cascades to produce HEU, a process which could take one to several months.  Once enough HEU is on-hand, it requires about 2-3 months to fashion this material into the cylindrical uranium metal that forms the core of a weapon. The arithmetic leads us back to Panetta’s timeline.

Panetta went on to say: “We think we will have the opportunity once we know that they’ve made that decision, to take the action necessary to stop (the program).” History is on his side.  There has been no country in the world that has produced a nuclear weapon without the United States knowing about the program ahead of time.  In the specific case of Iran, the U.S. and its allies have caught Tehran red-handed twice, exposing both of its covert nuclear enrichment facilities to the world. Iran is being watched 24-hours a day, seven days a week, by the most advanced intelligence and surveillance technologies the world has ever seen.  International inspectors are on the ground in Iran on an almost continuous basis.  If Ayatollah Khamenei made the decision to “break-out” and rapidly build a nuclear weapon, he would face a high risk of setting off the trip wire that would likely prompt immediate U.S. action.

The more likely route Iran will take in the near-term is a slow, methodical, and meticulous climb to reach the threshold of a weapon without triggering an attack, and all the while stay within the grey zone of international law.   In this respect, recent statements by Iran that it may develop nuclear submarines, which would require a higher form of enriched uranium, bears watching.

Joe Costa is a Truman Security Fellow