A reader spells out a realist case:

It goes something like this: the real leaders of Iran are wealthy, well-heeled men, not unlike the Saudi royals. These Ayatollahs are relying on Ahmadinejad to project a frightening and unpredictable image for Iran abroad, but it is not their prime intention to destroy Israel. Rather, Iran's leaders seek to consolidate power in the Middle East in the wake of America's disastrous Iraq policy. Ahmadinejad's pronouncements are meant only to keep the world off balance until the current instability in the region is resolved. To the extent that Iran is fomenting chaos in Iraq, it is doing so only to assist those politicians and religious figures - such as Muqtada al-Sadr - it views as crucial allies in the region. Once these allies have assumed control in Iraq, Iran will, in fact, become an agent of stability in Iraq. Iran's eventual goal is the formation of an alliance with Iraq that will amount to a Shiite superstate in the Middle East. (To the extent that Iran pursues nuclear weapons, it does so in support of this broad goal - rather than a specific goal to destroy Isreal.) 

The realist position holds that once Shiite control of Iraq has been realized - and Iraqi oil begins to flow - Iran will select from two possible courses of action: either work within established political/economic structures, such as OPEC and the U.N., to consolidate power on a global scale, or, begin allying itself with non-Western industrial powers, such as Russia and China, to challenge the West's political and economic hegemony more radically. The worst case scenarios in the realist vision are too numerous to count: the breakdown of the world's established economic and political systems, resource wars, unstable geopolitical alliances similar to those that led to WWI and WWII, etc.  Conversely, a realist may hope that all of this could also lead to a benign reshuffling of Middle East power - with the Shiite allies seizing some of the Saudis' control over the region without any real impact on the existing global structure. Under the latter scenario, we would find an empowered Iran willing to "play ball" with the West, once power has been secured.

And so the question, it seems to me, comes down to 9/11. Did it reveal a genuinely new and apocalyptic element in global politics, something made more terrifying by the advance of destructive technology? Or was bin Laden a fluke or a marginal figure? Do he and Ahmadinejad represent the real power in the Middle East, or are they just showmen, creating spectacles to distract the frustrated masses, while other, more serious figures wait in the wings, prepared to deal? On the answer to that question a great deal depends.

For me, this week, five years later, I believe the threat is real and growing. And I believe we have to fight, rather than accommodate, it. It seems to me we can be shrewd and deft and guileful in fighting it on our terms. Fighting does not merely mean brute military force. It can mean more skillful global diplomacy with other great powers to isolate Iran's regime, better counter-insurgency tactics in Iraq and Afghanistan, covert military action, expanded intelligence, as well as subtle but real support for the people of Iran. I'm afraid that under this president none of this will happen, which is why the next two years of continued Western incompetence are so perilous. But no American president can or should tolerate the Iranian regime's acquisition of nuclear weaponry. And negotiating with theo-fascists is a mug's game. Their God does not negotiate. And they are nothing if not faithful to their God.

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