Sens. Bob Corker, right, and John McCain are both unhappy with how the Obama administration is handling Iran.AP Photo

Frustration with the Obama administration’s handling of Iran is reaching a boiling point on Capitol Hill, even as Republicans acknowledge their limitations in trying to stop it.

With implementation of a controversial nuclear deal with Iran underway, the country has dominated the news over the last week: First capturing and releasing 10 Navy men who inadvertently entered Iranian waters after 16 hours, then releasing five American hostages in a prisoner exchange for seven of their own and finally, on Saturday, meeting sufficient requirements in curbing its nuclear program to receive sanctions relief from the United States and its allies.

The mixed bag of news out of Tehran has many in the GOP reiterating their longstanding concerns with the nuclear deal, and even some Democrats are raising eyebrows about Iran’s intentions. But in the wake of the deal, which passed through Congress last summer despite Republican efforts to stop it, there’s little that Congress can do unilaterally to curb any future bad actions by Iran.

Senate Republicans are hampered by an administration they don’t trust; a United Nations that, they say, essentially ignored an October missile test by Iran that violated a 2010 ban; allies in Russia and China, as well as Europe, that they don’t trust to follow through on additional sanctions against Iran, should they be needed in the future; and a regime in Tehran that they see as increasingly testing its power as it benefits from new sanctions relief.

“Frankly right now there’s not a hell of a lot we can do because [the U.S. and its allies] just freed up $100 million to the Iranians,” Sen. John McCain said Tuesday. “We’ll pay a very, very heavy price for that in the future.”

McCain referenced the 10 American Navy sailors who were photographed in Iranian custody with their hands over the backs of their necks, kneeling down, a photo he carried around with him during the Republican Party’s retreat in Baltimore last week. “I’m amazed, with their hands behind their necks and the secretary of State says that it’s really a great thing. It’s one of the most disgraceful chapters in U.S. history,” McCain said Tuesday. “I mean, the [footage] of American service members on their knees, that was spread everywhere in the Middle East. That was one of the great propaganda triumphs that the Iranians have ever had.”

“We’re in a really bad place,” Senate Foreign Relations Committee chairman Bob Corker said Wednesday.

Corker, who fought stridently to block the Iran nuclear deal last year, expressed frustrations with the deal in a committeewide hearing on its implications for the Middle East Wednesday morning. But in an interview later in the day, Corker argued that Congress isn’t completely without recourse.

The Senate is expected to take up a reauthorization of the Iran Sanctions Act, which expires late this year, in the next few months, sending a signal to the Iranian regime and providing a key tool for the administration to reinstate sanctions against the country should they fail to hold up to the standards of the nuclear deal.

The administration pushed back against Congress’s desire to renew ISA late last year, warning that it could put the nuclear deal in jeopardy. But senators say that now that Implementation Day has arrived in Iran, they believe the administration will support them in moving forward on a reauthorization.

As part of the nuclear deal, the United States has not done away with sanctions against Iran, but merely paused them allowing the administration to, in Washington’s terms, “snap back” sanctions should the country violate the deal.

Sen. Robert Menendez, a Democrat who was also highly critical of the Iran deal, argued Wednesday that early passage of a new ISA bill is important so that the U.S. will “have something to snap back to.” Menendez argued that it will take months to alert and prepare the nation’s allies to implement new sanctions on Iran, should they become necessary. “It’s a year, easy,” Menendez said.

Corker said that it’s very possible that Congress could levy new sanctions against Iran in addition to ISA this year, adding that particularly “if activities continue as-is, I’m sure there’ll be a lot of bipartisan support.”

But for any sanctions to go through, they’ll need the support of President Obama, who negotiated the nuclear deal with Iran that he’s hailed as “historic progress through diplomacy” in the Middle East. The Obama administration has said it will support reauthorization of ISA before its expiration in 2016, but it's unclear what the fate of other sanctions would be.

Further complicating that mission is the feeling, particularly among Republican members, that the P5+1 coalition that secured the deal with Iran (which includes the U.S., China, France, Russia, the United Kingdom as well as Germany) will not be there to support the U.S. in levying additional sanctions if and when the time comes.

“I mean you’ve got China and Russia that consider Iran to be an ally. China’s sending them equipment, Russia’s working with them in Syria. I don’t anticipate they’re ever going to join in in any kind of snap-back, I just don’t see it happening,” Corker said Wednesday. “And we have European quote [un]quote ‘friends’ who are so desirous of doing business with Iran, I think it’s going to be difficult there too.”

“Now Iran has the leverage both from the standpoint of already having all of their resources, but in addition to that knowing that we’re not going to get unity in this P5+1,” Corker added.

Sen. David Perdue of Georgia, a freshman member on the committee, took that a step further, citing it as one of his major concerns about the Iran deal moving forward. “The coalition’s already gone away. It’s pretty obvious, the coalition’s gone away,” Perdue said. “So the snap-back provision of this Iran nuclear deal was always built around, well if they violated [the deal], we’ll just snap-back the sanctions. It’s not going to be that easy and I think the proof is on the table now.”

In closing Wednesday’s hearing, Corker said that it will be important for Congress to continue put pressure on the administration, both to hold Iran accountable and to come up with a more “comprehensive” strategy in the region.

“I think it’s going to be difficult—very, very difficult in the future to push back in any meaningful way against any violations that take place,” Corker said.

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