I left this comment over at Foreign Affairs too.

This article attempts to diffuse much of the urgency surrounding the fears of a nuclear armed Iran by saying that there is no guarantee it would result in the proliferation of similar technology in the rest of the Middle East.

While this could be accurate, it seems to be part and parcel of a pollyanaish view.

While the author is no doubt correct that previous dire predictions of nuclear proliferation have proven to be overwrought and did not pan out as anticipated, that does not mean it is destined to continue.

Given that access to technology, in particular since the conclusion of the Cold War, has become much easier- it seems more likely now than in the past that proliferation will take place at a faster pace than the historical norm.

Between the Khan network and ambiguous activities by North Korea, it seems presumptious to assert that just because proliferation has not happened in the past, or because it took 20 years from the first "bomb" to the "Chinese bomb" that this pattern will persist.

Additionally, the U.S. failure to prevent a nuclear armed Iran (which is pretty much a fair accomplie at this point) will, indeed make others in the rgion nervous. While it is possible that Arab nations will seek accomodation with Iran or will trust American security "guarantees", it only would seem prudent for them to look at their own counters and hedge their bets. Between the Persian/Arab divide and the Sunni/Shia divide, there is a lot of tension in the Middle East with Iran now firmly in the center.

The U.S. should re-examine its concepts of deterrence for this situation. It must be prepared to navigate the complexity of multipolar nuclear powers in multiple regions of the world.

If this view turns out in 20 years to have been overly pessimistic, what is the harm in having been prepared? If it turns out to be accurate, what is the harm in being caught flatfooted?

The concern over the "nuclear domino theory" should remain of paramount importance. Prudence dictates that the worst case scenario be envisaged and contingencies prepared for it.