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A team of inspectors from the International Atomic Energy Agency - the IAEA - has completed two days of talks in Tehran. But they did not get to visit a site that might have revealed whether Iran plans to build a nuclear bomb. It's just the latest complication in the conflict over Iran's nuclear ambitions. More talks are scheduled, but NPR's Tom Gjelten says 2013 is likely to be the year the U.S. decides whether to go to war with Iran.
TOM GJELTEN, BYLINE: For more than five years now, U.S. intelligence agencies have said they don't know whether Iran wants to develop a nuclear weapon. President Obama has promised he won't allow it. The implied threat is that he's prepared to order military strikes to block Iran from building a bomb. And the president should know the moment Iran makes that move. The sign would be when it starts enriching uranium to the level of purity necessary for a bomb. So far, Iran has not crossed that line. David Albright is a nuclear ex pert who has worked with the IAEA.
DAVID ALBRIGHT: It's the time once they decide, OK, we're going to start making weapon grade uranium, before they have enough for a bomb. Even when you have 13,000 centrifuges, it just takes time to make that material. We think the president would know in time to take military action.
GJELTEN: But that's based on the inspectors' view of the situation now. There's concern that Iran has a secret underground facility where additional enrichment may take place. Plus, the Iranians are building more and more centrifuges; those are the machines used to enrich uranium. It wouldn't take the Iranians as much time now to produce enough material for a bomb as it would have taken them a year or two ago.
ALBRIGHT: There's worry that Iran will reach a point of capability, and we would estimate mid-2014 right now, that they will be able to break out so quickly that the IAEA may not be able to sound a warning in time to take preventive action.
GJELTEN: If that timeline is right, the United States and its allies have only about a year and a half before they'll have no opportunity to block Iran from building a bomb, should it decide to do so. The hope is that in the meantime a deal can be struck, that the pain of sanctions will induce the Iranians to suspend some of their enrichment activity. They've already purified some uranium to the 20 percent level - unacceptable, in the Western view. Reza Marashi, research director at the National Iranian American council, says a deal should be possible.
REZA MARASHI: Whether it's enriching to the 20 percent level, their underground nuclear facility, those things can all be negotiated, but for the right price.
GJELTEN: An end to sanctions, perhaps. But negotiations take trust. Marashi says Iranians fear that U.S. hard-liners don't actually want a deal, that they see the current government in Tehran as a repressive regime and want it overthrown.
MARASHI: That's the overarching concern of the Iranian government, that the policy of the United States is regime change. There are key officials in the regime that have thought since day one after the 1979 revolution. So, disproving that theory in their mind is a Herculean task.
GJELTEN: If the Iranians think the United States is just out to smash their government, they have little reason to give up the option of building a nuclear weapon and negotiate. David Albright says the United States and Western governments need to make clear their goal is not regime change.
ALBRIGHT: The threat of military strikes is that if you build the bomb you will get struck militarily, not if you have 10,000 more centrifuges, or we don't like what you've just done to part of your population.
GJELTEN: There wasn't much progress on negotiations during the U.S. presidential campaign, when President Obama had to worry about not appearing tough. And in June, Iran is set to have a presidential election of its own. Politics, says Reza Marashi, has a way of interfering.
MARASHI: When you have over three decades of not talking, when you have over three decades of politicians in both Washington and Tehran making careers out of proving how nasty they can be to the other side, it gets very difficult for leaders, both in a democracy like ours and in an authoritarian regime like theirs, to be willing to take risks for peace. It's much easier to escalate the conflict.
GJELTEN: What's worrisome, Marashi says, is that both sides are now running out of escalation options and they're running out of time. Tom Gjelten, NPR News, Washington.