

Obtaining weapons-grade high-enriched uranium (HEU) is the most difficult and technically challenging obstacle to acquiring a nuclear weapon.

Sanctions, direct action, and diplomatic tools have neither changed Iran’s nuclear policy nor had a visible effect on the enrichment program, including the growing stockpile of 19.75% LEU. Iran is at the threshold of a nuclear weapons capability. This assessment is version 2.1 of a recurring analysis of Iran’s nuclear program. Iranian President Ahmadinejad visits the Natanz uranium enrichment facility on April 8, 2008.
