Reuters

The Obama administration managed to strike a preliminary deal with the regime in Tehran following difficult, intense negotiations, only to discover that securing the cooperation of Congress may be equally challenging.

No sooner had negotiators stepped up to a podium in Lausanne, Switzerland, to announce a framework—well, maybe just the broad outlines of a framework—for a nuclear deal with Iran than the backlash began. Republicans are blasting the deal, complaining that President Obama and Secretary of State John Kerry, his chief negotiator, gave far too much away to the Iranians and have created a deal that is porous, unenforceable, or simply credulous.

Many of the critics reached immediately for the analogy of the 1938 Munich Agreement between Britain's Neville Chamberlain and Adolf Hitler. (James Fallows has written on the limits of that analogy.) Take Bill Kristol, the neoconservative pundit and longtime critic of negotiations with Iran:

Senator Mark Kirk, the Republican who holds Obama's former seat from Illinois, went in the same direction, saying, "Neville Chamberlain got a better deal from Adolf Hitler."

Speaker John Boehner, who is on a trip to the Middle East and met Wednesday with Israeli Prime Minister Benjamin Netanyahu, was also critical of the deal:

After visiting with our partners on the ground in the Middle East this week, my concerns about Iran’s efforts to foment unrest, brutal violence and terror have only grown. It would be naïve to suggest the Iranian regime will not continue to use its nuclear program, and any economic relief, to further destabilize the region.  

In particular, Boehner worried about removing sanctions on Iran. "Congress must be allowed to fully review the details of any agreement before any sanctions are lifted," he said.

Marco Rubio, a Republican leader in the Senate on foreign policy, was similarly skeptical of the deal. "I look forward to hearing from administration officials what specific terms Iran has agreed to as part of what was supposed to be a comprehensive framework agreement, but the initial details appear to be very troubling," he said. "This attempt to spin diplomatic failure as a success is just the latest example of this administration’s farcical approach to Iran."

And so the list went on, with Republicans lining up to blast the agreement, even though many of its details remain unclear, as too weak. But Obama didn't get a great deal of support on his side of the aisle, either. Some consistent Democratic critics of the administration's approach were predictably skeptical. Senator Bob Menendez, who temporarily stepped down as ranking member of the Foreign Relations Committee after being indicted for corruption Wednesday, issued a statement that emphasized the role of Congress in reviewing and consenting any deal.

But even Senate Minority Leader Harry Reid offered a carefully measured reaction, stopping well-short of endorsing the arrangement:

I am cautiously optimistic about this framework. We must always remain vigilant about preventing Iran from getting a nuclear weapon but there is no question that a diplomatic solution is vastly preferable to the alternatives.

Now is the time for thoughtful consideration, not rash action that could undermine the prospects for success. We have much to learn about what was negotiated and what will take place between now and the end of June. In the coming days and weeks, we should all take a deep breath, examine the details and give this critically important process time to play out.

Speaking in the Rose Garden shortly after the deal was announced in Switzerland, Obama struck a defensive note, as if to preempt his critics. "This is a deal between Iran, the United States of America, and the major powers in the world—including some of our closest allies," he warned. "If Congress kills this deal—not based on expert analysis, and without offering any reasonable alternative—then it’s the United States that will be blamed for the failure of diplomacy."

The president noted, as he has before, that these domestic critics as well as foreign ones like Benjamin Netanyahu lack one crucial thing: a plausible alternative to the negotiated deal.

But most of the reaction so far seems choreographed—it was preordained the hawkish critics would detest the deal, and that Obama would insist they had no other option. For now, however, so few details of the deal are clear that it's hard for either side to make a careful case in support of its view.

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