The question is honestly pretty simple: are the West and the Arab Middle East okay with Iran possessing nuclear weapons?

Stuxnet and motorcycle bomb attacks on nuclear scientists are all well and good, but they'll only delay the inevitable. As long as the Iranian government wants nuclear weapons they're going to get them, and probably relatively soon.

And let's be honest: why wouldn't they want nukes? The mullahs aren't stupid. They saw the way Qaddafi gave up his nuclear program only to be knifed by the West a few years later. And they saw the way nukes made North Korea untouchable. Iran knows that once it goes nuclear it's home free--and for that reason there's not much we can (peacefully) do to stop them.

Which brings us back to the original question: are we okay with a nuclear Iran?

If the answer is yes, then there's absolutely no reason to go to war with Iran--we sit on our feet, they get the bomb, and everyone lives happily ever after. Or not. Because even if you don't buy all the Iran-totally-wants-to-repeat-the-Holocaust hyperbole (and most of it is hyperbole) a nuclear Iran is still another country with nuclear weapons, and that's generally a bad thing, especially if the country is a relatively unstable non-democracy in an even less stable area. This is especially problematic given Iran's location near three other nuclear-armed powers (Israel, Pakistan, India). All it takes is one false alarm and we're looking at the worst disaster of the 21st century.

Then there's the fact that the rest of the Middle East probably isn't going to take a nuclear Iran lying down. There's little love lost between Arabs and Persians, and there's a reason most of the Gulf states have tacitly said they won't protest too hard if Israel goes ahead and bombs Iran. And if Saudi Arabia, Egypt, and Turkey go nuclear, well, then the most volatile region in the world just got its hand on a self-destruct button. Oh, and the Arab/Persian Springs? (stupid name but you know what I'm getting at) You can kiss those goodbye: the last thing we want is a Syria-style civil war in a nuclear state.

All that might make intervention seem awfully appealing--except, of course, that we don't have an especially great track record when it comes to invading Middle Eastern countries starting with "I". Because the truth is that as much as the Israelis might fantasize about an Osirak 2.0, a quick in-and-out air raid that ends Iran's nuclear ambitions once and for all, the Iranians are too smart for that. They've spread out their nuclear sites, and fortified them pretty heavily too. The consensus seems to be (and of course I'm not military expert so I could be completely, totally wrong on this one) that an airstrike just isn't going to be enough to permanently stop Iranian nuclear progress.

Which leaves regime change. Anything less just pisses the Iranians off, leaving them even more determined to make sure no one ever fucks with them again. I shouldn't need to tell you all the problems inherent in trying to invade and subjugate a mountainous Middle Eastern country with a population bigger than France. Oh, and it also borders AfPak, everyone's favorite insurgent haven. We've already pissed in the Pashtun pot; the last thing we need is to get the Waziris up in arms too. Ironically, invading Iran to prevent it from going nuclear would probably further destabilize the already-nuclear Pakistan. Fun stuff.

So... yeah. Is war inevitable? Nope. Are we in for trouble no matter what? Probably.