General Petraeus and President Bush may well be right that groups in Iran are supporting and arming factions in Iraq. Their suggestion that some Iranian leaders dream of building nuclear weapons may also be true. What makes their charges so frightening, though, is their evident belief that these transgressions may justify an American attack on Iran. Such an attack would strengthen militant factions in Iran rather than weakening them; make Iran more dangerous rather than less; and undermine US national security rather than strengthening it.
