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The task before the secretaries of state, energy and treasury is what you might call a heavy lift - convincing skeptical lawmakers that the Iran nuclear agreement is a good deal that they should support. The trio made their case today before a key panel, the Senate Foreign Relations Committee. NPR's Ailsa Chang begins our coverage.
AILSA CHANG, BYLINE: To be clear, the nuclear deal doesn't need Congress's permission to take effect, but what opponents can do to kill it is pass legislation that stops the White House from lifting sanctions imposed by Congress. Secretary of State John Kerry warned the consequences of that would be dire.
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JOHN KERRY: The result will be the United States of America walking away from every one of the restrictions that we have achieved and a great big green light for Iran to double the pace of its uranium enrichment, proceed full speed ahead with a heavy water reactor, install new and more efficient centrifuges.
CHANG: Kerry and other White House officials are now enmeshed in a high-intensity lobbying blitz on Capitol Hill to secure support for the agreement. And Senate Foreign Relations chair Bob Corker says they're pushing a false choice on lawmakers.
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BOB CORKER: With every detail of the deal that was laid out, our witnesses successfully batted them away with the hyperbole that it's either this deal or war.
CHANG: In other words, accept this deal or prepare to use military force to prevent Iran from getting a nuclear weapon. Up until now, Corker has maintained he wouldn't reflexively denounce the accord like many of his fellow Republicans, but today it seemed he'd made up his mind.
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CORKER: Not unlike a hotel guest that leaves only with a hotel bathrobe on his back, I believe you've been fleeced.
CHANG: And with that line, he joined a chorus of Republicans, like Jim Risch of Idaho, who piled on some more.
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JIM RISCH: To be able to walk away from this and say that this is a good deal is ludicrous. With all due respect, you guys have been bamboozled.
CHANG: Since nearly every Republican is expected to oppose the agreement, the White House lobbying efforts have focused on Democrats, many of whom say they're still undecided. That includes the top Democrat on the Foreign Relations Committee, Ben Cardin of Maryland.
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BEN CARDIN: We don't trust Iran, but we've got to leave emotion out of this. We've got to look at the agreements, and we've got to determine whether the compliance with this agreement by the United States will put us on a path that makes it less likely or more likely that Iran will become a nuclear weapon power.
CHANG: For Cardin, the concerns are several. Will the inspections be robust enough? If Iran cheats, how long before it finishes building a nuclear weapon? And how quickly could the U.S. take action?
One Democrat says, not quickly enough. Bob Menendez of New Jersey wants to extend sanctions that will expire in 2016 so those sanctions can snap back immediately if Iran violates the deal.
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BOB MENENDEZ: I don't understand how we ultimately have a credible belief that snapback means something if in fact you're not going to have the ability to have those sanctions in place.
CHANG: Another persistent concern on both sides has been the tantalizing phrase, anytime, anywhere inspections. Lawmakers insist that's what they were promised, but today Energy Secretary Ernest Moniz said, not so.
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ERNEST MONIZ: I did say the words anytime, anywhere, and I'm very pleased that yesterday a member of your caucus acknowledged, however, that the full sentence was, anytime, anywhere, in the sense of a well-defined process with a well-defined end time.
CHANG: Republican presidential candidate Marco Rubio of Florida had no patience for such caveats. He told Kerry, there's no guarantee the deal will survive past the current president.
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KERRY: There's no alternative that you or anybody else has proposed as to what you...
MARCO RUBIO: I sure have, Secretary Kerry. I have.
KERRY: ...And I am confident that the next president of the United States will have enough common sense that if this is being applied properly, if it's being implemented fully, they're not just going to arbitrarily end it.
CHANG: Lawmakers have until September 17 to accept or reject the deal. Ailsa Chang, NPR News, the Capitol. Transcript provided by NPR, Copyright NPR.