German Foreign Minister Frank Walter Steinmeier, European Union High Representative Federica Mogherini, Iranian Foreign Minister Javad Zarifat, Russian Deputy Political Director Alexey Karpov and British Foreign Secretary Philip Hammond are seen following nuclear talks at the Swiss Federal Institute of Technology in Lausanne (Ecole Polytechnique Federale De Lausanne) April 2, 2015. (Pool/Reuters)

JANE HARMAN

President and chief executive of the Woodrow Wilson International Center for Scholars.

Kudos to the indomitable John Kerry — he has found the recipe for a “good enough” deal. Iran’s nuclear bomb program has been stopped, hopefully forever. The major question mark is sanctions relief; on that point President Obama needs and will benefit from bipartisan input from Congress, which wields critical leverage and remains deeply skeptical. Now comes another opportunity to forge a closer relationship with Congress. The president must work with Sens. Bob Corker (R-Tenn.) and Ben Cardin (D-Md.) to shape bipartisan legislation that will get our country to “yes” on a sanctions package most people will support. If Obama can pull that off, it could have a spillover effect for cooperation on other legislation critical to our national security: trade, cybersecurity and surveillance reform, to name a few. Nothing excuses Iran’s bad behavior in Yemen and through proxies such as Hezbollah and Hamas, which is exactly why it’s praiseworthy that non-nuclear sanctions will remain in place. Still, given Iran’s dismal track record, many remain understandably hostile to any deal. But to paraphrase Winston Churchill, this is the worst deal — except for all the others.

This comment has been revised by the writer since it was originally published.

DENNIS ROSS

Fellow at the Washington Institute for Near East Policy. Former special assistant to President Obama.

No negotiations with the Iranians are easy. The difficulty in producing the framework understanding is a reminder that filling in the details will also prove to be an ordeal. While the framework includes important limitations on the Iranian program, the Iranians will resist the scope of the verification that the Obama administration will need in a final deal.

And that is key. By making the central measure by which to judge the effectiveness of the deal a one-year breakout time, the administration has made verification the most important part of the agreement. It must be in a position to show that it can detect what the Iranians are doing, when they are doing it. International Atomic Energy Agency (IAEA) inspectors must have access to declared and undeclared sites — even if it is at a military or Revolutionary Guard facility. Will the Iranians permit that? Will we have the same understanding of what the verification regime requires? I suspect that will be a difficult issue to resolve.

The tension between our need to show that Iran’s capabilities have been constrained and the Iranian desire to show that it will be treated like any other member of the Nuclear Non-Proliferation Treaty will bedevil the talks until the end. But that is to be expected in a negotiation that is about limiting Iran’s capabilities and not being able to show that the intent of the Iranian nuclear program has changed.

JOE CIRINCIONE

President of the Ploughshares Fund.

It is not very often that we get to see the hinge of history move. We just did. The Lausanne breakthrough is a major win for U.S. national security.

We had three key objectives and can now achieve them all: Block all of Iran’s pathways to a bomb; lock in tough inspections to catch Iran, should it try to break or sneak out; and keep our coalition united to enforce the deal.

We got them all — and more. The agreement will slash Iran’s nuclear program, freeze it, lock it up and put it under a microscope. Iran will have to rip out two-thirds of its centrifuges. It will cut its stockpile of uranium gas by 97 percent. It will not be able to make any uranium or plutonium for a bomb. Some restrictions continue for 25 years — an entire generation.

Our diplomats and experts must have time to finish the job. If Congress passes inept new sanctions and restrictions, the whole deal will crumble. We will be blamed; the sanctions regime will collapse; Iran will ramp back up all the work that negotiations have kept frozen for the past 17 months.

We will then have to either allow an unconstrained nuclear program or start a war with one of the largest military powers in the Middle East.

This deal is by far the best of all possible options.

DANIELLE PLETKA

Senior vice president for foreign and defense policy studies at the American Enterprise Institute.

The outlines of a “comprehensive” deal with Iran to slow its quest for nuclear weapons are now public. Almost every previously “unacceptable” aspect of the program has become acceptable, and the Islamic republic will continue to enrich uranium, operate and modernize its heavy-water reactor, likely conceal the military dimensions of its program and stonewall the IAEA on key issues, all with the blessing of the United States.

Other than the obvious outcome — an Iran with nuclear weapons at some point in the not-too-distant future — two points bear noting: The first is that, for an administration that professes its affection for international law and regimes, this agreement will signal the death knell of the Nuclear Non-Proliferation Treaty. Iran used the treaty’s terms to pave the way toward nuclear weapons status, successfully defied the treaty’s enforcement agency and the U.N. Security Council and will not be held accountable for violating its international obligations. By acquiescing in Iran’s use of the treaty to facilitate nuclear weapons proliferation, the administration is effectively signing off on a road map that others in the region — led by Saudi Arabia — have made clear they intend to follow to protect themselves from the Iranian nuclear threat.

The second is that the artificial deadline the administration imposed, at least in part to deflect congressional efforts to impose additional sanctions on Iran, had the perverse effect of pressuring President Obama and Secretary of State John F. Kerry, and not the Iranian government, to make concessions. On almost every key issue, the Iranians won the day. The entire infrastructure of the Iranian nuclear weapons program (not to speak of its terrorist apparatus or efforts to destabilize the Middle East) remains intact. And the irony is, this administration has decided to throw in its lot not with the representatives of the American people in Congress or our allies in the region but with the leadership in Tehran. As Kerry said, a “big day” indeed.

OLLI HEINONEN

Former IAEA deputy director general. Senior fellow at Harvard University’s Belfer Center for Science and International Affairs.

It appears that 5,000 centrifuges would remain at Iran’s Natanz plant, with stocks of uranium, affirming Iran’s status as a nuclear-threshold state. Albeit the breakout time would be a year, but the concerns of Iran’s neighbors would not disappear. Several countries in the Middle East are building their nuclear infrastructure. Efforts to get commercial suppliers to establish regional uranium-enrichment services as an alternative to domestic efforts will not get much traction under the circumstances likely to play out from the Mediterranean beaches to the Gulf of Aden and Basra. There will not necessarily be a race to a bomb, but countries will be climbing the ladder of nuclear capabilities.

Iran will also continue research and development on more advanced centrifuges, which could further reduce its breakout time. But the underground facility in Fordow will be converted to a nuclear research center without uranium enrichment, which should set some minds at ease. The framework calls for full disclosure of Iran’s current and past nuclear activities. That requires unfettered access by IAEA inspectors to all relevant sites — including military sites, which have played a pivotal role in Iran’s nuclear efforts.

It was difficult for the parties to develop a joint framework. The challenges ahead on the details are not going to get any easier. Nothing is agreed until everything is agreed.

RAY TAKEYH

Senior fellow at the Council on Foreign Relations.

The framework agreement announced by the United States and Iran is a more substantial document than the vague general statement that was anticipated. The two sides have engaged in serious negotiations. Still, there are lingering issues and dueling narratives to consider. Iranian media accounts claim that all U.N. Security Council sanctions, European Union measures and critical U.S. financial sanctions would be removed upon the completion of a final agreement. The United States is more vague on these critical issues. The Iranians insist that the sunset clause is 10 years, while the Americans say some restrictions would persist for another five. The differing interpretations are worrisome.

The concerns that have plagued this interim agreement — the Joint Plan of Action — are thus not entirely alleviated. Iran would maintain a substantial enrichment capacity. The Fordow plant that President Obama once insisted must be closed would remain open, and Iran’s massive stockpile of enriched uranium would not be shipped to Russia for reprocessing but would be diluted somehow. The verification regime, though enhanced, would still operate within the parameters of the Nuclear Non-Proliferation Treaty and its managed access provision. That means that inspectors would have to rely on Iran’s consent to examine a given facility, particularly military ones. The previous military dimensions of the program are neglected while ballistic missiles are ignored altogether. And of course, the agreement has an expiration date, at which time Iran can build an industrial-size nuclear program.

At best, this agreement, should it be concluded, will have frozen some aspects of Iran’s program, while anticipating its enlargement once the deal expires.

KARIM SADJADPOUR

Senior associate at the Middle East Program of the Carnegie Endowment for International Peace.

Perhaps an apt metaphor for the framework agreement is a marriage engagement. The wedding is scheduled to take place at the end of June. The coming months will see vigorous debate about the size of the dowry and the terms of the prenuptial agreement. If past is precedent, the wedding date could well be postponed, and many parties — in Congress, Israel, the Arab world and Tehran — would like to sabotage it. If and when the wedding takes place, the success of the marriage will be assessed in the years to come. The bride doesn’t trust the groom. The groom doesn’t trust the bride. But for now the engagement should be celebrated. Based on the U.S. version of the agreement, it looks stronger than many anticipated. If the Iranians are working off the same document, it will be very difficult for critics of the agreement to argue they have a better alternative.