The Iran nuclear deal was officially implemented on Saturday, as Iran successfully fulfilled its initial key nuclear commitments and the international community relieved major sanctions, including unfreezing about $100 billion of Iranian money. Implementation Day was met with applause from deal supporters in the U.S. and Iran, while critics have raised questions about whether Iran will adhere to its requirements and how it will flex its newfound economic power. Also in recent days, the U.S. and Iran agreed to a prisoner swap that led to the freedom of Washington Post reporter Jason Rezaian and others, and negotiated the release of American sailors detained in Iran. What does the arrival of Implementation Day mean for Iran’s nuclear program and nuclear nonproliferation, and how does it bode for the future of U.S.-Iran relations? We asked Belfer Center experts to weigh in on these and related questions.

The International Atomic Energy Agency released its “final assessment” yesterday of the possible military dimensions of Iran’s nuclear program.

Matthew Bunn, Co-Principal Investigator of the Project on Managing the Atom, discusses his perspective towards the Iranian nuclear agreement. He describes how the deal restricts Iran's nuclear program, giving the world time to continue to respond to the Iranian challenge, and how the agreement, while not perfect, is a significant step in rolling back aspects of the Iranian program. He suggests that while mutual hostility handicapped talks, the presence of technical experts alongside political officials was crucial in having the final agreement come together. he suggests that while the deal may not solve all problems in US-Iran relations, it does leave the door open to future cooperation on issues of mutual concern.

Matthew Bunn, Professor of Practice and Co-Principle Investigator of the Project on Managing the Atom at the Belfer Center, is a signatory on the Arms Control Association's statement on the framework agreement between the P5+1 and Iran. The statement argues the framework released so far is a positive step for nonproliferation, and that it will help put in place the necessary verification and monitoring measures to prevent Iran from racing towards a bomb without detection, and urges support for the finalizing of the agreement.

Matthew Bunn, Professor of Practice and Co-Principle Investigator of the Project on Managing the Atom at the Belfer Center, writes in The National Interest that if we consider a "good deal" to be an agreement that reduces Iran's chances of building a nuclear bomb more than alternative options, then the current framework announced at Lausanne is a good deal. He argues that the deal includes stringent technical terms that will make any breakout attempt much more detectable, and also notes that politically the deal decrease the immediate military threat to Iran, diminishing the need for a nuclear bomb, while sanctions relief will create economic disincentives to returning to the nuclear confrontation. Finally, he suggests that the alternatives to a deal, such as a return to sanctions and pressure or a military attack, are much less likely at this point of achieving the goal of an Iran without a nuclear weapon.

In all the fierce arguments over the pros and cons of the recent nuclear deal with Iran, a key element has mostly gotten lost: what does it actually say?  Here’s a quick summary of what each side gets out of the deal.  (You can find the official White House summary here, though Iran has asserted that certain parts of it are inaccurate – as discussed further below.)  In essence, this deal was never designed to do more than (a) stop each side from getting much worse off while negotiation of a broader deal continued, and (b) send a signal that meaningful agreements are possible, despite the enormous mistrust and hostility on both sides.  It does both of those things pretty well – but it leaves a lot of heavy lifting for the future.  The deal should be understood in combination with the similarly partial agreement Iran reached with the International Atomic Energy Agency (IAEA) earlier in November.

The Israeli writer Ari Shavit had a piece in the November 20 New York Times that asserted that the proposed first-stage deal with Iran “would guarantee” that Iran would eventually build a nuclear bomb.  I think he’s completely wrong, for reasons I explained in an op-ed of my own in the Christian Science Monitor.