Author: Greg Thielmann and Robert Wright

The Trouble With “Breakout Capacity”How a widely misunderstood term could doom the Iran nuclear negotiations

This article was published in collaboration with Slate.

For better or worse—and probably for worse—negotiations to peacefully resolve the standoff over Iran’s nuclear program may hinge on a single technical term: “breakout capacity.”

“Breakout capacity” refers to the time it would take to produce enough highly enriched uranium for a nuclear weapon, should Iran at some point decide to build one. The term isn’t formally part of the negotiations that resumed in Vienna this week between Iran and the P5+1 (the five permanent members of the U.N. Security Council, plus Germany). Rather, negotiators discuss things like how many centrifuges Iran should be allowed to keep as part of a peaceful nuclear energy program. But back in Washington, when people in Congress and elsewhere argue over what constitutes an acceptable deal, they talk in terms of breakout: How much breakout capacity would Iran have if left with a given number of centrifuges, or a given amount of some other variable under negotiation?

It’s a valid question. All the more unfortunate, then, that so many people—including politicians, pundits, and policy analysts—are so confused about it.