An Iranian woman and her son walk past Shahab-2 (L) and Shahab-3 missiles on display in front of a large portrait of Iran's Supreme Leader Ayatollah Ali Khamenei in a square in south Tehran. Atta Kenare | AFP | Getty Images

President Donald Trump has made up his mind about how he will seek to toughen a historic international accord to limit Iran's nuclear program, according to the White House. "The president's reached a decision on an overall Iran strategy. He wants to make sure that we have a broad policy to deal with that, not just one part of it," White House press secretary Sarah Huckabee Sanders told reporters on Tuesday. Trump will elaborate on details of the plan later this week, Sanders added. The Washington Post previously reported the president will deliver his decision on Thursday. According to multiple reports, Trump will refuse to certify to Congress that the landmark 2015 Iran nuclear deal remains in the U.S. national security interest. Yet he is expected to stop short of encouraging lawmakers to immediately reimpose sanctions, and instead try to coerce Europeans and Iranians back to the negotiating table.

There's a combination of hubris and ignorance that is pushing advocates of the strategy to believe we left things on the table, and the Iranians are waiting to give it up if we apply pressure. Richard Nephew Columbia University Center on Global Energy Policy research scholar

That will require the Trump administration to apply enough pressure to bring reluctant partners and a hostile adversary in line. But it must also exercise enough restraint to avoid pushing either beyond the breaking point. Some analysts see a straight line to a stronger accord, while others warn there is only a narrow path for success that runs through a minefield. The United States worked with China, France, Germany, Russia and the U.K. from 2013 to 2015 to stop Iran's progress toward building a nuclear weapon. The resulting deal, named the Joint Comprehensive Plan of Action, lifted sanctions that had hobbled Iran's economy in exchange for limits on the country's nuclear program and inspections of Iranian facilities. That has allowed Iran to rebuild its oil export business and line up companies eager to invest in its energy industry. The deal also carved out an exception to allow American aircraft maker Boeing to sell planes to Iran. Trump and foreign policy hawks are now seeking additional concessions from Iran on key parts of the deal. They are also trying to curb Iran's support of U.S.-designated terrorists, its ballistic missile program and its intervention in regional conflicts — issues that were not directly addressed by the JCPOA.

'Major American pressure campaign'

Mark Dubowitz, CEO of the Foundation for Defense of Democracies, says he expects the administration to pursue a multistage strategy that begins with decertification by the Oct. 15 deadline. Trump would then seek to bring Congress and European leaders on board with measures to pressure Iran, according to Dubowitz, a long-time critic of the JCPOA who is familiar with the administration's thinking. "What Iran is going to face now is the roll out of a major American pressure campaign using all instruments of national power to neutralize and roll back Iranian aggression," he told CNBC. That may include economic and financial power, covert actions and political warfare, he said. In his view, the administration will seek to address three major issues: the expiration of key aspects of the deal, obtaining access to military sites and reining in Iran's ballistic missile program. It will also likely target Iran's Revolutionary Guard Corps, a hard-line military group, with sanctions for the first time.



But some say the gap between what Iran is willing to concede and what the Trump administration aims to achieve is simply too wide.

The likelihood that the Iranians give any ground is "pretty low," while the odds that they budge on anything meaningful is "almost infinitesimal," according to Richard Nephew, a research scholar at Columbia University's Center on Global Energy Policy who served as lead sanctions expert for the U.S. team that negotiated the deal. Nephew says it's possible that international negotiators could have secured a slightly tougher deal, but he rejects the notion that the Obama administration made an agreement out of desperation. He asserts that U.S. negotiators pushed for the most stringent measures in the opening months of negotiations. "There's a combination of hubris and ignorance that is pushing advocates of the strategy to believe we left things on the table, and the Iranians are waiting to give it up if we apply pressure," he said. Nephew said Trump cannot exert much more pressure on Iran, in part because Europeans do not back the administration's strategy. "Pressure is the currency of diplomacy, so if you don't bring more, you're not going to be able to buy more concessions."

Bringing Europe to the table

To be sure, French President Emmanuel Macron has floated sanctions over Iran's ballistic missile test, as well as talks over Iran's regional provocations and how to proceed once certain provisions of the nuclear deal expire. The threat that Trump would undercut the deal by signaling the United States might pull out initially gave the administration some leverage over Europeans, according to Suzanne Maloney, deputy director of foreign policy at the Brookings Institution. Some European leaders and diplomats had hoped to reduce that threat by offering to do more to counter Iran's behavior in the Middle East, she said. Decertifying is not a major step, she said, but it opens the possibility that Iran will respond in kind to U.S. pressure and ultimately jeopardize the accord. "I think it creates a set of circumstances in which the Europeans are that much less likely to try to placate the administration because this is the eventuality they were hoping to forestall," said Maloney, who served in President George W. Bush's State Department and advised senior Obama officials on Iran.

If Congress imposes new sanctions that look suspiciously like those the United States lifted under the JCPOA, Iran could walk away from the deal, Maloney warned. "In effect we just begin a process that has real unintended consequences in terms of potentially driving the Iranians out of the deal and creating the conditions for its slow erosion over time," she said. Dubowitz rejects the notion that Europeans are focused on decertification, or that it diminishes U.S. leverage over the Continent. "It's all a diplomatic dance, but the reality on the ground is the Europeans want above all to preserve the deal, and the fear that Trump or Republicans will walk away from the deal has motivated them to now look at ways to fix it," he said. What Europeans fear most, he says, is the prospect of a U.S. or Israeli strike on Iran's nuclear facilities, so-called secondary sanctions that can lock European firms out of the U.S. market and dollar transactions, and the type of multibillion-dollar fines slapped on European banks by U.S. regulators in recent years. "All of those fears have been heightened under a president they believe is much more willing to use coercive American power," he said.

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