Iran may well make good on some of its threats to lash out at American interests and targets, should U.S. President Donald Trump move forward with decertifying the landmark 2015 Iran nuclear deal.
Iranian Foreign Minister Mohammad Javad Zarif on Wednesday pledged a "tougher" response if Trump decides to find Tehran is not in compliance with the nuclear deal, according to the state-run IRNA news agency. An Iranian military spokesman further promised this week that his country’s forces would teach the U.S. "new lessons” if needed.
But current and former U.S. intelligence and military officials say any Iranian action is unlikely to be carried out directly and that such behavior would not be a dramatic departure from Iran’s behavior since the nuclear deal, the Joint Comprehensive Plan of Action (JCPOA), went into effect.
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“The trajectory that we have seen Hezbollah on has continued pretty much unabated throughout the duration of the conflict in Syria,” National Counterterrorism Director Nicholas Rasmussen told reporters Wednesday, as the U.S. announced a new round of actions aimed at countering the Iranian-sponsored terror group.
Rasmussen is only the latest in a long line of U.S. officials to voice concern about Iran’s activities since the nuclear agreement went into effect.
'Clearly the top threat'
Just last month, the head of U.S. Central Command called Iran “clearly the top threat” to long-term stability in the Middle East.
“They operate almost entirely in what we refer to as the gray zone, that space between normal international competition and armed conflict,” Gen. Joseph Votel said during an appearance in Washington.
And White House officials say Iran has become increasingly aggressive, even as the U.S. continued to certify the regime’s compliance with the deal.
“What they’re doing now more than ever is accelerating the arming of their proxies,” National Security Adviser H.R. McMaster told a forum in Washington last month.
The agreement signed by Iran and the five permanent members of the United Nations Security Council plus Germany, requires Tehran to sharply restrict its nuclear program and allow more access to international inspectors. Iranian leaders also promised not to seek, develop or acquire nuclear weapons.
In return, Iran received relief from crippling economic sanctions, including the release of billions of dollars in frozen overseas assets and re-admittance to the international banking system.
“It is the worst deal,” McMaster said. “It didn’t address clearly critical capabilities Iran is still free to develop.”
And there has long been suspicion that Tehran has been using financial flexibility as a result of funds freed up under the terms of the nuclear deal – estimated $50 billion to $150 billion – to expand the scope and reach of its proxy forces across the Middle East and beyond.
With few signs Iran is willing to modify its behavior, officials say the U.S. has no choice but to take a more aggressive approach to weaken Iran’s widening influence, even if the results are not immediate.
"The Iranians are concerned about this (decertification),” said Michael Pregent, a former U.S. intelligence officer now with the Hudson Institute. “It calls them out for their behavior. It punishes them for their behavior.”
Pregent said the U.S. would also be wise to designate Iran’s elite Revolutionary Guards Corps (IRGC), whose commanders often embed with proxy forces, as a terrorist organization.
“Putting sanctions on the IRGC and other entities constrains Iranian actions, constrains other countries from supporting Iran,” Pregent said.
Experts who track Iran’s proxies say few seem to have felt any constraints until now.
“In September, the [anti-U.S.] rhetoric was upped by Kata'ib Hizballah, one of the IRGC's most loyal creations,” said Phillip Smyth, a University of Maryland researcher who follows the online activity of Iranian-backed Shi'ite militias in Iraq and Syria.
“They were talking about targeting U.S. forces in Iraq,” Smyth said, describing it as “the usual rhetoric.”
Still, there are those who worry decertifying the nuclear deal and designating the IRGC as a terrorist group, will only make U.S. efforts to contain Iran more difficult while making its proxies more dangerous.
“Decertification will support the Iranian narrative that the U.S. is distrustful and may persuade Iranian militias to target U.S. service members as they did during the Iraq War,” said Nicholas Glavin, an independent researcher formerly at the U.S. Naval War College's Center on Irregular Warfare and Armed Groups.
“Iranian militias will continue to exert a significant amount of control in parallel to American troops’ attempts to stabilize Iraq and Syria," Glavin said.