It is unimaginable that the United States would have to contribute hundreds of billions of dollars and highly unlikely that we would have to contribute even tens of billions of dollars.

The basic problem with the Non-Proliferation Treaty is there's no teeth in it, no penalties for countries that don't comply. Worse, as you say, the very naïve structure of the NPT has actually made it helpful for countries who want to acquire nuclear weapons. Iraq, North Korea, Iran, all used the NPT to build up their nuclear programs.

The Iranians are very skilled terrorist, and we'd have to expect that they'd hit at us as hard as they could. Especially in Iraq, where they have a great deal of power and influence.

Most Iranians are sick and tired of revolutions. They've had one for the last 25 years, and they don't want another one. Those who've tried to spark another revolution have failed time and again. I don't think there's any evidence that somehow, if the U.S. gave these guys the high sign, it would make regime change somehow more likely. Every time the U.S. has tried to interfere in Iranian affairs to help a particular group of Iranians, it's backfired on us, and hurt the group we tried to help.

In the United States, Iran is nothing but a whipping-boy. Few Americans have any real use for Iran. Most of us, what we know and remember about Iran are things like the hostage crisis in 1980, or they think about the Iranian attacks in Lebanon, or on the Khobar Towers. So you don't get a whole lot of political mileage in the United States by going out and advocating better relations with the Iranians.

It is unimaginable that the United States would have to contribute hundreds of billions of dollars and highly unlikely that we would have to contribute even tens of billions of dollars.

The real concern is that Iran would do what Pakistan did. Pakistan wanted nuclear weapons, like Iran, purely for defensive reasons - to defend itself against India. The problem was that once Pakistan acquired the weapons, it allowed the country to be more aggressive. So they stepped up their support for the Kashmiri terrorists, and it led very quickly to the Kargil crisis in 2000, which almost sparked a nuclear war between India and Pakistan.