AFTER WE CONCEDE THEY CAN, WILL THEY?:

The real question for ourselves is whether we should change our approach to diplomacy with Iran, now that a new Iranian president has advertised his desires to end Iran's isolation and the sanctions imposed on it, and to repair the "wound" that he has said exists between the United States and the Islamic Republic.

Until now, we have taken an incremental, confidence-building approach within multilateral negotiations with Iran, but they have probably already run their course. Indeed, while our side (the United States, China, Russia, Germany, Britain and France) negotiated with Iran on and off for the last several years with no results, the Iranians were dramatically expanding the numbers of centrifuges they had installed to enrich uranium. They now have roughly 17,000 and have succeeded in upgrading to a new generation of far more efficient centrifuges.

Those developments have shrunk the time we have available to ensure that the Iranians cannot break out and present the world with the fait accompli of a nuclear weapons capability. So we may have time for diplomacy, but not a lot.

We should move now to presenting an endgame proposal -- one that focuses on the outcome that we, the United States, can accept on the nuclear issue. And we should do so even if our negotiating partners -- particularly the Russians -- aren't prepared to accept such a move, since the clock is ticking. We should give Mr. Rowhani a chance to produce, but the calendar cannot be open-ended.

Diplomacy often boils down to two simple elements: taking away excuses for inaction and providing explanations for a deal that could be struck. On the first point, the Iranians say they don't know what we will accept in the end. The answer should be that we can accept Iran's having civil nuclear power but with restrictions that would make the steps to producing nuclear weapons difficult, as well as quickly detectable. Our offer should be credible internationally; if Iran was not prepared to agree to it, the Iranians would be exposed for not being ready to accept what they say they want. Indeed, if we make a credible proposal that would permit the Iranians to have civil nuclear power with restrictions, it would allow them to save face for themselves: they could say the proposal was what they had always sought and that their rights had been recognized.

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