This article is from the archive of our partner National Journal

President Obama got word late Monday afternoon that after 18 days of grueling talks, the final details of a nuclear deal with Iran had been completed. His national security team went to brief him on the specifics of the historic agreement, but he waved them away.

He wanted to hear it from John Kerry, who has spent nearly a month in Vienna as the lead negotiator for the U.S., all while on crutches, nursing a broken leg from a bike accident in May. Obama called his secretary of State to congratulate him—and got the welcome news that a deal had been reached, a senior administration official told reporters on a conference call Tuesday.

It was the culmination of an intense period of uncertainty for global security, as well as Obama's foreign policy legacy. After missed deadlines and reports that Iran had reneged on the framework agreed upon at an April summit in Lausanne, Switzerland, the accord was a gratifying reward for the administration.

Obama announced the news, a "comprehensive long-term deal" to severely curb Iran's ability to obtain a nuclear weapon, in a statement from the White House on Tuesday morning—and issued a strong warning to Congress he won't let it block the agreement from being implemented.

"Today, because America negotiated from a position of strength and principle, we have stopped the spread of nuclear weapons in this region," he proclaimed at the White House with Vice President Joe Biden at his side.

The deal "meets every single one of the bottom lines we established when we achieved a framework" in talks earlier this spring, he said. That includes prohibiting Iran from producing the highly enriched uranium and plutonium necessary to build a nuclear weapon, supervising the machines used to enrich uranium, and greatly reducing its stockpile of uranium—down to what it would take to build just one bomb.

To ensure that Iran abides by the agreement's restrictions, inspectors from the International Atomic Energy Agency will have 24/7 access to the country's main nuclear facilities, as well as the whole of its nuclear supply chain.

"This deal is not built on trust," Obama said. "It is built on verification."

The toughest words were for the home audience, as Obama made a heavy push for Congress to approve the agreement, encouraging opponents of it to, "consider what happens in a world without this deal."

"Without this deal, there is no scenario where the world joins us in sanctioning Iran until it completely dismantles the nuclear program," he said. "Nothing we know about the Iranian government suggests that it would simply capitulate under that kind of pressure, and the world would not support an effort to permanently sanction Iran into submission. We put sanctions in place to get a diplomatic solution."

Congress has 60 days to review the agreement, but Obama left no doubt where he stands.

"I will veto any legislation that prevents the successful implementation of this deal," the president said.

Speaking directly to the deal's avowed opponents in Congress, he proactively admonished that "it would be irresponsible to walk away." He also compared the situation to the arms control agreements negotiated with the Soviet Union during the Cold War, noting that "you don't make deals like this with your friends."

"Our national security interests now depends upon preventing Iran from obtaining a nuclear weapon," he said. "Without a diplomatic resolution, either I or a future U.S. president would face a decision about whether or not to allow Iran to obtain a nuclear weapon or to use our military to stop.

"No deal," he added forcefully, "means a greater chance of more war in the Middle East."

Critics in Congress have vowed to vote down the accord in favor of additional sanctions on Iran. The purpose of sanctions, however, was to come to a diplomatic solution.

"History shows that when we just walk away from the table, and impose sanctions, that in no way serves as a check on Iran's nuclear program," the senior administration official said. "They steadily advance their nuclear program under sanctions. Ultimately, sanctions helped pressure them back to the table."

Shortly after Obama finished speaking Tuesday, members of the Senate Foreign Relations Committee weighed in on the agreement. Sens. Tim Kaine of Virginia and Christopher Coons of Delaware, both Democrats, articulated the need for a strong agreement that cuts off every route Iran has to building a nuclear weapon, and said they would support the deal only if it ensured that.

Foreign Relations Committee Chairman Bob Corker said he a statement that he starts out the review process "from a place of deep skepticism that the deal actually meets the goal of preventing Iran from obtaining a nuclear weapon."

"In the coming days, Congress will need to scrutinize this deal and answer whether implementing the agreement is worth dismantling our painstakingly constructed sanctions regime that took more than a decade to establish," he said. "Iran continues to be the lead sponsor of terrorism in the world, and relieving sanctions would make the Tehran regime flush with cash and could create a more dangerous threat to the United States and its allies."

But Obama isn't worried about critics in Congress, the senior administration official told reporters.

"Frankly, he's confident that it exceeds what we thought we could get at the beginning of this process," the official said. "And so he is welcoming a debate here about the quality of this deal."

As for the other chief critic of the deal—Israeli Prime Minister Benjamin Netanyahu, who Tuesday morning called it "a historic mistake"—the president plans to speak to the Israeli leader, but has not yet done so.

"They have clear differences about this deal, there's no question about that," the official said. "But given the nature of our relationship with Israel, and our commitment to their security, he will certainly want to have that conversation."

This article is from the archive of our partner National Journal.

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