Watch the live stream: The House of Representatives is expected to vote on a resolution on war powers against Iran

WASHINGTON (AP) — The House of Representatives is poised to vote Thursday on a war powers resolution to stop President Donald Trump’s attack on Iran, a sign of unease in Congress over a rapidly expanding conflict that is reordering U.S. priorities at home and abroad.

The House of Representatives reconvenes at 10 a.m. EST. Watch the live stream in our video player above.

This is the second vote in as many days, after the Senate rejected a similar measure along partisan lines. Lawmakers face the surprising reality of representing the American people in wartime and all that entails — with lives lost, dollars spent and alliances tested by the president’s unilateral decision to go to war with Iran.

He watches: Senate GOP votes against war powers resolution after US-Israeli strikes on Iran

The result in the House of Representatives is expected to be close, but the outcome will provide an early glimpse into political support for, or opposition to, the US-Israel military operation and Trump’s rationale for bypassing Congress, which alone has the authority to declare war.

“Donald Trump is not a king, and if he believes war with Iran is in our national interest, he should come to Congress and make his case,” said Representative Gregory Meeks, the top Democrat on the House Foreign Affairs Committee.

Meeks said that in his three decades in Congress, the toughest votes he got were deciding whether to send American troops to war.

The roll calls are a clarifying moment for the president and the parties just days after a foreign conflict that quickly carried echoes of the long U.S. wars in Afghanistan and Iraq. Many veterans of those wars have since run for office and now serve in Congress.

Republicans largely support Trump, and most Democrats oppose the war

Trump’s Republican Party, which narrowly controls the House of Representatives and the Senate, believes that the conflict with Iran is not the beginning of a new war, but rather the end of a regime that has been threatening the West for decades. The operation led to the killing of Iranian Supreme Leader Ayatollah Ali Khamenei, which some see as an opportunity for regime change, although others warn of a chaotic power vacuum.

Rep. Brian Mast of Florida, the GOP chairman of the House Foreign Affairs Committee, publicly thanked Trump for taking action against Iran, saying the president is using his constitutional authority to defend the United States against the “imminent threat” the country poses.

Mast, an Army veteran who worked as a bomb disposal expert in Afghanistan, said the war powers resolution effectively required “that the president do nothing.”

For Democrats, Trump’s war with Iran, influenced by Israeli Prime Minister Benjamin Netanyahu, is a war of choice that tests the balance of power in the US Constitution.

“The Framers were not messing around,” said Representative Jamie Raskin, Democrat of Maryland, arguing that the Constitution is clear that only Congress can decide questions of war.

Whether lawmakers support or oppose the Trump administration’s military action, they should have the discussion, he said. “It’s up to us. We have to vote on it.”

While views in Congress largely align along party lines, there are intersecting coalitions. The House and Senate resolutions were bipartisan, with bipartisan support and opposition. The council is also voting on a separate resolution affirming that Iran is the largest state sponsor of terrorism.

A war powers resolution, if signed into law, would immediately halt Trump’s ability to wage war unless Congress approves military action. The president is likely to veto the measure.

As an alternative, a small group of Democrats proposed a separate war powers resolution that would allow the president to continue the war for 30 days before he would have to get approval from Congress. It is not expected to be voted on yet.

Trump officials offer shifting justifications for war

After launching a surprise attack on Iran on Saturday, Trump sought to win support for a conflict that Americans of all political stripes were already wary of entering. Trump administration officials spent hours behind closed doors on Capitol Hill this week trying to reassure lawmakers that the situation was under control.

Six US military personnel were killed over the weekend in a drone strike in Kuwait, and Trump said more Americans could die. Thousands of Americans rushed overseas for flights, many lighting up phone lines at congressional offices as they called for help trying to flee the Middle East.

Defense Secretary Pete Hegseth said the war could last eight weeks, twice as long as the president initially expected. Trump has largely left open the possibility of sending US forces to participate in an aerial bombing campaign. Hundreds of people died in the area.

The administration said the goal is to destroy Iranian ballistic missiles that it believes protect its nuclear program. She also said that Israel was ready to act against Iran, and that American bases would face retaliation if the United States did not strike first. The United States said on Wednesday that it had blown up an Iranian warship near Sri Lanka.

“This administration can’t even give us a straight answer as to why we’re launching this preemptive war,” said Rep. Thomas Massie, a Republican from Kentucky who is often an outsider to his party.

Massie and Rep. Ro Khanna, D-Calif., who teamed up to release the Jeffrey Epstein files, also forced a war powers resolution on the ground, overcoming earlier objections from House Speaker Mike Johnson.

Johnson warned that it would be “dangerous” to limit the president’s power while the US military is already in conflict.

Senators sit at their desks for the formal vote

In the Senate, Republican leaders succeeded, albeit narrowly, in defeating a series of war powers resolutions related to several other conflicts during Trump’s second term. But this was different.

Underscoring the gravity of the moment on Wednesday, Democratic senators filled the chamber and sat at their desks as voting began.

“Today every senator — every individual — will choose a side,” Senate Democratic Leader Chuck Schumer said before the vote. He asked, “Do you stand with the American people exhausted by eternal wars in the Middle East, or do you stand with Donald Trump and Pete Hegseth as they push us upside down into another war?”

Senator John Barrasso, the second-in-command of Republicans in the Senate, said, “Democrats would rather obstruct Donald Trump than eliminate Iran’s national nuclear program.”

The legislation failed by a vote of 47 to 53, mostly along party lines, with Republican Senator Rand Paul of Kentucky in favor, and Democratic Senator John Fetterman of Pennsylvania opposed.