Is Congress interfering on Iran – or just doing its job?

Taiwan. Cuba. And now Iran.

In all three cases, Congress has taken action aimed at weakening or countering presidential foreign policy decisions it rejected or did not wholeheartedly support.

When the United States recognized Beijing as the legitimate capital of one China, Congress passed the Taiwan Relations Act of 1979, requiring the president to sell military hardware and technology to Taiwan to provide for its defense.

When President Clinton took steps to ease relations with Cuba, Congress passed the Helms-Burton law in 1996 to strengthen the US embargo of Cuba.

Now, a Congress with sharp hostility toward the Iran nuclear deal and President Obama’s engagement with Iran is taking steps to toughen what it sees as a weak and obsequious policy – if not to kill the nuclear deal altogether.

Congressional grumbling about a president’s foreign policy is hardly rare, but actions that manage to constrain or scuttle a foreign policy initiative are unusual, experts say.

“It’s pretty infrequent,” says George Lopez, an expert in the use of economic sanctions at the University of Notre Dame in Indiana. The recent congressional action targeting Iran is “fairly unprecedented…. We usually don’t sign an agreement with a country one day, and then turn around and find new ways to punish it the next.”

This week the House approved legislation that would place new sanctions on Iran, though it requires a second vote later this month. Members of both houses of Congress, primarily Republicans, continue to press the White House to stop “placating” Iran and instead punish Iran for actions including recent missile tests. 

“We need to see more backbone, not more backing down,” Rep. Ed Royce, chairman of the House Foreign Affairs Committee, told journalists at the congressional Republicans’ annual retreat in Baltimore Thursday.

He accused the administration of not responding to two recent ballistic missile tests that violated United Nations resolutions, as well as evidence of arms transfers by Iran in the region. “We’ve got to change the perception that we’re going to get rolled on these violations,” Representative Royce said.

Mr. Obama has vowed to veto the bill.

The current actions are similar to Congress’s decision to reinforce the Cuban embargo just as Mr. Clinton was easing travel restrictions and facilitating family contacts, Dr. Lopez says. The legislation on Taiwan differed in that Congress was acting to bolster an ally potentially threatened by the US outreach to China.

Others go further, however, saying it is incongruous for Congress to undermine an Iran nuclear deal that it didn’t have the numbers to stop last summer.

“It is nothing less than bizarre that, at the very moment when Iran has followed through on its commitments to reduce its nuclear program, Congress would vote on legislation that could undermine the agreement and leave Iran unconstrained and closer to a nuclear weapon,” says Jim Walsh, an international security expert at the Massachusetts Institute of Technology in Cambridge.

As a result of actions required under the deal, “Iran for the first time in roughly a decade does not have enough nuclear material to build a bomb,” Dr. Walsh says. “Why in the world would members of Congress try to undo that success?”

“The simple answer is politics,” he adds.        

Others say it would be wrong to dismiss long-shot attempts by Congress to influence or alter foreign policy.

“I don’t see what Congress is doing now on Iran as just a protest vote,” says Lopez. “Certainly the people associated with this view it as serious legislative action.”

Lopez compares new Iran legislation with repeated attempts to kill the Affordable Care Act. On Friday, Obama vetoed a bill that would have abolished Obamacare. Republicans don’t have the votes to override the veto, but it was the first time such legislation made it to the White House.

“The fact that after multiple years of attempts [Obamacare opponents] were able to put a repeal of the ACA on the president’s desk and force a veto – some people call that futile,” he says. “But other people consider it the role of the legislature and something [congressional opponents] have to go through with.”

That brings up another way that congressional action on Iran and Obamacare are similar, Lopez says. The two issues bring out intense reactions from people.

“If you’re a strict constitutional analyst, this [action on Obamacare and Iran] is what Congress should do,” he says. “If you’re a contemporary analyst, you’re more likely to see a negative and revenge motif here.”

• Staff writer Francine Kiefer contributed to this report from Baltimore.