Iran's Nuclear Program: Isolation, Engagement, or Acceptance?

Iran appears to be playing a cat-and-mouse game with the International Atomic Energy Agency, claiming that its nuclear program is for peaceful civilian purposes. Yet the Iranians are proceeding to enrich uranium that could then be used to build nuclear weapons. Undersecretary of State John Bolton advocates isolating Tehran and has stated that the United States will not "allow America's national security to be dependent on the good faith of a group of fanatic mullahs seeking nuclear weapons." Some presidential rhetoric is eerily similar to language used very early in the run-up to the Iraq war. The Israelis have made it clear that they will never permit Iran to become a nuclear power and are reported to be buying 500 bunker-buster bombs from the United States. Is preemptive military action against Iran inevitable? What are the consequences of such action? Is engagement with Iran to create a nonproliferation regime a viable option? Are isolation and engagement the only policy choices? Is it possible for the United States to come to terms with a nuclear-armed Iran?