A preliminary agreement that would curtail Iran's nuclear program raised hope around the world that the nation could be prevented from developing nuclear weapons. But just 24 hours after the deal was struck, there appeared to be sharp disagreement over the details in the package.
The U.S. State Department outlined 43 specific points it said would limit Iran's inventory of enriched uranium, furlough its industrial equipment, convert a secret nuclear enrichment facility to a research center and create an inspection program to ensure future compliance. But the disclosure triggered a sharp retort by Iranian officials that the U.S. was spinning its own version of the framework agreement.
The exchange highlights the serious difficulties that the U.S. and five other world powers face in negotiating a detailed final agreement in an environment of deep distrust.
Nuclear weapons and arms control experts warned Friday that although the agreement looks good in principle, negotiating a legally binding document is likely to be harder than expected, particularly in the area of verification and inspections.
"There is no Iran agreement, but rather a statement of principles that has to be fleshed out," said Linton Brooks, a former U.S. nuclear weapons chief and the final negotiator of the first strategic arms limitation agreement between the U.S. and Russia. "Nothing is agreed to until everything is agreed to."
The deal is fuzzy on how world powers are going to punish any Iranian rule-breaking. That's a big issue to skeptics because all too often, rule-breaking in such agreements leads to tangled legalistic disputes rather than forceful response.
The U.S. made a number of major concessions in the proposed agreement, including giving up the hope of fundamentally dismantling Iran's nuclear program, which leaves Iran as essentially a threshold nuclear weapons power for as long as 25 years. Energy Secretary Ernest Moniz said that the deal would lengthen the time it would take Iran to develop a nuclear weapon to at least a year, rather than the two to three months it would now require.
The prospect of no agreement left world powers fearing a worse outcome.
"The present framework political deal is better than no deal," Alexei Arbatov, a Russian arms control expert whose work is published by the Carnegie Endowment for International Peace, wrote on the endowment's website. A failure of the negotiations, he said, "would make the new war in the [Persian] Gulf inevitable, with dire implications for international security and the nonproliferation regime."
Under the preliminary deal, Iran would mothball two-thirds of its newer high-speed centrifuges that enrich uranium, going from 19,000 devices to 6,104 older machines. It would reduce its stockpile of low-enriched uranium from 4,500 pounds to 136 pounds and not build any new facilities for enrichment for 15 years.
Forcing Iran to rely on the old machines should impose powerful restraints on Iran's ability to race to complete a bomb in the next decade "and likely beyond," Jodi Joseph, a former nonproliferation aide in the Obama White House, wrote in an email.
Iran can continue to enrich fuel, but only to a level useful for a commercial electrical power reactor. It would also be required to convert a reactor in Arak that can create plutonium, a key technical step in building a hydrogen bomb.
Iran hasn't conceded many of the details described in the State Department summary of the agreement. And officials haven't said how they plan to pare their uranium stockpile, whether by shipping the material to Russia, as they had apparently promised last year, or by diluting it or chemically modifying it. Exporting the material would give the outside world much greater reassurance that it would not be diverted for use as bomb fuel, many experts say.
Michael Elleman, a senior fellow at the International Institute for Strategic Studies and a former United Nations weapons inspector in Iraq, called it "the best agreement that could have been realistically achieved," but said he was concerned about the apparent absence of a tracking system for Iran's key nuclear program scientists and managers.
"In Iraq, we had access to everybody," he said. "If you can track everybody and where they are, it is very difficult to create a breakout program. The Iranians have been deceitful in the past. These are smart guys and they are resourceful."
But of all the details that must be worked out, nothing will be as difficult as an agreement on verification and inspection, U.S. experts said.
Brooks said the framework is similar to the summit statement that came out of the 1987 meeting between President Reagan and Soviet leader Mikhail Gorbachev.
"I finished negotiating the agreement four years later, and all of that time was spent on verification," Brooks said. "It is premature to make any final conclusion until you see the details. If all of the things in there [the State Department summary] were done, it is a pretty good deal."
U.S. officials involved in the talks say the Iranians have been generally cooperative so far on inspections and monitoring.
The Iranians have argued that the six powers should use transparency, not rolling back the program, to make sure they don't get the bomb.
Siegfried Hecker, former director of Los Alamos National Laboratory, said the verification procedures outlined in the U.S. fact sheet are rigorous and it is "quite surprising that Iran agreed to them, (if they have).
"Suspicions will linger for years because of the mistrust," he said in an email.
Philip Coyle, a former deputy director of Lawrence Livermore National Laboratory, chief of nuclear weapons testing and a recent advisor to the Obama administration, recalled that Soviet Union officials repeatedly accused the U.S. of attempting to spy on them during verification inspections, calling it a form of "legalized espionage."
The strategic weapons treaties between Russia and the U.S. involved hundreds of inspections and massive investment in technology to verify that the agreements were being upheld. Russian military officials and their U.S. counterparts made detailed visits to each others' weapons plants and military installations.
"Verification is always difficult in any agreement or treaty and if there is not a lot of trust to start with, it makes it all the harder," Coyle said.