And this is the "optimistic" scenario, for those who dismiss Iran's genocidal threats against Israel as mere rhetoric, or who ignore the likelihood of multiple Arab countries seeking their own nukes in response.

I suspect that many who argue that an Iranian nuke is inevitable or even desirable cannot honestly dispute these anticipated consequences. For example, in his post claiming that Iran "needs" nuclear weapons, Hossein Derakhshan admits that he "argued that possessing nuclear weapons would embolden the new government of Iran, which was already exhibiting an unimpressive record on democracy and human rights."

Derakhshan says he changed his mind because the U.S. "is behaving more and more like a reckless imperial force." Why is another nation's alleged bad behavior grounds for shooting oneself in the foot?

In his own post Derakhshan also suggests that if Iran normalized relations with Israel and the U.S. then the world would "tolerate a nuclear Iran." This implied admission shows the real direction of cause and effect: If Iran stopped threatening other countries and building up terrorist militias (in Lebanon, Iraq, and Gaza) then the West would -- to the detriment of the Iranian people's struggle for freedom -- leave the regime in Tehran alone.

The real argument is not over the merits of Iranian nuke but what can still be done about it. Bill Emmott says it's too late: "Sanctions, after all, will be just a pin-prick. ... Any sanctions that the UN Security Council can agree to won't be very tough in any case." Maybe, but why is it written in stone that the West will fail to learn the lessons of the 1930s and appease rather than defend itself?

The Iranian regime can still be forced to back down, possibly without firing a shot, so long as draconian sanctions are backed the credible threat of force and by support for the human rights of the Iranian people. Such a course is not without costs and risks, but these pale beside the price we will pay for staying on our current path of indecision.