At the root of the problem of how to respond to Iran’s nuclear progress is the inscrutability of Iran itself. The Iranians hid their nuclear work from inspectors for 18 years, and last spring, in arguing against an Israeli attack, the Americans cited the probability that many of Iran’s nuclear facilities are still hidden. The Israelis had argued that an attack would set back the nuclear program by at least three years; the Americans responded that its effect might last as little as six months.
