Senate Thwarts Bid to Curb Trump’s War Powers on Iran

Republicans on Wednesday blocked a measure that would limit President Trump’s power to continue waging war against Iran without congressional authorization, turning back a bid by Democrats to insist that Congress weigh in on a sweeping and open-ended military campaign.

The 53-to-47 vote against taking up the measure was almost completely along party lines, reflecting a deep partisan divide on the Iran war as the Senate delivered the first clear test of congressional resolve since the joint U.S.-Israeli strikes, Operation Epic Fury, began across Iran four days ago.

Senators Tim Kaine, Democrat of Virginia, and Rand Paul, Republican of Kentucky, tried to force action on the measure. They invoked a provision of the 1973 War Powers Act, which requires that resolutions to terminate offensive hostilities be considered under expedited procedures.

Mr. Paul was the only Republican leading the effort, and no other G.O.P. senators joined him in support of the measure.

Senator John Fetterman of Pennsylvania was the only Democrat to break with his party and vote against the resolution, in keeping with his vocal stance in support of Israel and reluctance to place limits on the president’s authority to act in its defense.

The measure’s failure came as the administration offered varying and at times conflicting explanations for the war, raising questions about its legality and posing a dilemma for some lawmakers as they were called upon to register a position on a conflict that has already cost American lives. It also comes only months before the midterm elections and as polls show the conflict is deeply unpopular.

“Americans want President Trump to lower prices, not drag us into unnecessary forever wars,” Mr. Kaine said ahead of the vote. “Yet he has unilaterally launched strikes at Iran without congressional authorization.”

Mr. Kaine introduced the resolution with Mr. Paul in January as the president was directing the largest military buildup in the Middle East since the war in Iraq and shortly after Mr. Trump said that the United States was “locked and loaded and ready to go” ahead with military action against Iran in response to a violent crackdown on protesters there.

Republicans have largely praised Mr. Trump’s decision to launch the military campaign, which has killed Ayatollah Ali Khamenei, Iran’s supreme leader, along with a number of his deputies and senior advisers. They argue that the action was justified given Iran’s decades of targeting Americans through its own forces and proxy terror groups throughout the region.

Senator Roger Wicker of Mississippi, the Republican chairman of the Armed Services Committee, on Wednesday said that he grieved “the six American servicemen and women who’ve died in the fighting” and added that he was also mourning “the thousands of Americans that have died over the last 47 years at hands of the brutal Islamists.”

The president understands “the weight of war,” Mr. Wicker added, lauding his decision to begin strikes as “profound, deliberate and correct.”

Senator Mitch McConnell, Republican of Kentucky, spoke in favor of the military campaign, saying during a speech on the Senate floor that “the Islamic Republic of Iran was, quite literally, founded on the premise of existential war against America and against Israel. And over and over again, it has escalated the war, exported more terror, spilled more blood and destabilized an entire region.”

But he cautioned that his support for executive authority was not boundless, adding that the president has a responsibility to make sure the use of his authority is “judicious, rooted in core national interests and broadly supported by the American people.”

Some other Republicans who opposed the resolution also suggested their position could shift if the military action expanded or dragged on.

Senator Josh Hawley, Republican of Missouri, said on Wednesday that his support for the operation could flag if it were to expand beyond aerial strikes.

“I’ve always drawn a line at ground troops,” he said, adding that if Mr. Trump sought to deploy them, that would “require some sort of authorization.” He has also emphasized the need for continued briefings as the campaign continues to unfold and widen in scope.

Hours before the vote, Defense Secretary Pete Hegseth and Gen. Dan Caine, the chairman of the Joint Chiefs of Staff, said that the U.S. military was overwhelming Iran with aerial strikes and that a more intense phase of the campaign had begun as more bombers arrived on Wednesday.

Iranian leaders, Mr. Hegseth said, were looking up at the skies “and seeing only U.S. and Israeli air power, every minute of every day until we decide it’s over. And Iran will be able to do nothing about it.

“Death and destruction from the sky, all day long.”

General Caine said that the campaign had devastated Iran’s ballistic missile program and its naval fleet, and that it continued to make “steady progress” with plans to “expand inland, striking progressively deeper into Iranian territory.”

The conflict has, so far, resulted in the deaths of at least six American service members, a sobering reminder that this conflict is remarkably different than other military actions Mr. Trump has undertaken since his return to office, which allies on Capitol Hill have praised as limited in scope and resulting in no American casualties.

Wednesday’s vote marked the latest in a series of failed war powers resolution efforts in both the House and Senate since Mr. Kaine began a series of challenges after Mr. Trump carried out a series of strikes against nuclear sites in Iran last summer. Since then Democrats have tried, and failed, repeatedly to rein in the president’s ability to act without consulting with Congress.

While the Constitution grants Congress the power to declare war, it has not done so since World War II, and the president has authority to act in defense of the nation. Over the last several decades, Congress has approved authorizations for the use of military force, which confer the executive with powers to direct military action without an immediate need to consult with the legislative branch. During his first term, Mr. Trump cited a Bush-era authorization that was used to justify a wide range of military actions over many years as legal grounds for a drone strike that killed Iran’s Maj. Gen. Qassim Suleimani in Baghdad in 2020.

This time, the president’s letter to Congress did not point to any previous authorization as justification and instead referenced the president’s “responsibility to protect Americans and United States interests both at home and abroad” without citing any specific or imminent threat.

A similar measure is expected to receive a vote on Thursday in the House, where it is also expected to fail.

Some Republicans who said Congress should have had a greater role in the decision to go to war against Iran nonetheless argued that removing U.S. forces at this stage would place American lives at risk.

“I will say very clearly: Yes, I wish I would have been consulted. I wish my vote would have been asked for before this,” said Senator John Curtis, Republican of Utah. “But the president did act within his legal bounds to do what he has done.”

Voting to halt the operation, he added, “is not the right answer to this.”

But the Democrats insisted that even if the mission was worthy, Congress had to step up and reassert Congress’s constitutional prerogatives on matters of war.

“I believe the founders’ worst fears have come to pass,” Senator Adam B. Schiff of California, one of the Democrats who cosponsored the resolution, said ahead of the vote. “Donald Trump has become too fond of going to war, and has done so again without congressional authorization.”

Megan Mineiro contributed reporting.