Does Israel have the ability to conduct a military attack against Iran's nuclear facilities similar to its 1981 strike on Iraq's Osirak reactor? The Israeli Air Force has significantly upgraded its equipment since the early 1980s, but the Iranian nuclear complex is a much harder target than was the Osirak reactor. Iran has three facilities that are critical for nuclear weapons production: a uranium conversion facility, an enrichment facility, and a heavy-water production plant and associated plutonium production reactor. This article analyzes possible interactions of Israel's improved air force, including the addition of F-15I aircraft and U.S.-supplied conventional “bunker-buster” precision-guided munitions, with the Iranian target set and air defense systems. It concludes that Israel has the capability to attack Iran's nuclear infrastructure with at least as much confidence as it had in the 1981 Osirak strike. Beyond the case of Iran, this finding has implications for the use of precision-guided weapons as a counterproliferation tool. Precision-guided weapons confer the ability to reliably attack hard and deeply buried targets with conventional, rather than nuclear, weapons. Intelligence on the location of nuclear sites is thus the primary limiting factor of military counterproliferation.