As the shouting about the interim deal has subsided, the analytical community has begun examining more carefully the details of what was agreed—and what was left out. Because the Iranian nuclear challenge is inherently so complex and involves inescapable technicalities that really matter, translating the sometimes mind-numbing details of SWUs, centrifuge operating efficiencies, and units of UF6 or oxide into criteria that are understandable for policymakers and critics is demanding. 

At the risk of tooting Belfer Center horns, we note two recent contributions that make the technical morass more intelligible.

Chart 1 below illustrates the difference between LEU (low-enriched uranium, used to make fuel for power plants) and MEU (medium-enriched uranium that can be used to make fuel for research reactors). On the path to HEU (high-enriched uranium that can become the core of a bomb), 20 percent enriched uranium (MEU) is much closer to bomb-usable material than 5% enriched uranium (LEU).

“Push ‘em back, way back”

Chart 2 assesses the interim agreement using this same criterion. The deal between the U.S. and Iran requires Iran to eliminate its current stockpile of almost a bomb’s worth of MEU (after further enrichment). This, in effect, pushes Iran back from the U.S.’ 10-yard line to the 30. While football fans know that having an opponent on one’s 30-yard line is not comfortable, they also know the probability of scoring from the 30 is far smaller than scoring from the 10.

In more precise technical terms, chart 3, from Belfer Center Senior Fellow Olli Heinonen, was published last week by Business Insider.

David Albright, who regularly tracks Iran’s nuclear progress, highlights in the Washington Postanother “plus” of the deal: “Iran will also be delayed in reaching the point where it has sufficient centrifuges and enriched uranium to produce, undetected, enough weapons-grade uranium for a bomb.”