WASHINGTON – President Donald Trump’s bombardment of three sites in Iran quickly sparked debate in Congress over his authority to launch the strikes, with Republicans praising Trump for decisive action even as many Democrats warned he should have sought congressional approval.

“Well done, President Trump,” Sen. Lindsey Graham of South Carolina posted on X. Alabama Sen. Katie Britt called the bombings “strong and surgical.” The Senate Armed Services Committee chairman, Roger Wicker of Mississippi, said Trump “has made a deliberate — and correct — decision to eliminate the existential threat posed by the Iranian regime.”

The instant divisions in the U.S. Congress reflected an already swirling debate over the president’s ability to conduct such a consequential action without authorization from the House and Senate on the use of military force. While Trump is hardly the first U.S. president to go it alone, his expansive use of presidential power raised immediate questions about what comes next, and whether he is exceeding the limits of his authority.

“This was a massive gamble by President Trump, and nobody knows yet whether it will pay off,” said Rhode Island Sen. Jack Reed, the top Democrat on the Senate Armed Services Committee.

Democrats, and a few Republicans, said the strikes were unconstitutional, and demanded more information in a classified setting. Senate Democratic Leader Chuck Schumer of New York said that he received only a “perfunctory notification” without any details, according to a spokesperson.

“No president should be allowed to unilaterally march this nation into something as consequential as war with erratic threats and no strategy,” Schumer said in a statement. “Confronting Iran’s ruthless campaign of terror, nuclear ambitions, and regional aggression demands strength, resolve, and strategic clarity.”

House Democratic Leader Hakeem Jeffries said that Trump “misled the country about his intentions, failed to seek congressional authorization for the use of military force and risks American entanglement in a potentially disastrous war in the Middle East.”

The quick GOP endorsements of stepped up U.S. involvement in Iran came after Trump publicly considered the strikes for days and many congressional Republicans had cautiously said they thought he would make the right decision. The party’s schism over Iran could complicate the GOP’s efforts to boost Pentagon spending as part of a $350 billion national security package in Trump’s “big, beautiful” tax breaks bill, which is speeding toward votes next week.

“We now have very serious choices ahead to provide security for our citizens and our allies,” Wicker posted on X.

House Speaker Mike Johnson, R-La., and Senate Majority Leader John Thune both were briefed ahead of the strikes on Saturday, according to people familiar with the situation and granted anonymity to discuss it. Thune said Saturday evening that “as we take action tonight to ensure a nuclear weapon remains out of reach for Iran, I stand with President Trump and pray for the American troops and personnel in harm’s way.”

Johnson said in a statement that the military operations “should serve as a clear reminder to our adversaries and allies that President Trump means what he says.”

House Intelligence Committee Chairman Rick Crawford, R-Ark., said he had also been in touch with the White House and “I am grateful to the U.S. servicemembers who carried out these precise and successful strikes.”

Breaking from many of his Democratic colleagues, Sen. John Fetterman of Pennsylvania, an outspoken supporter of Israel, also praised the attacks on Iran. “As I’ve long maintained, this was the correct move by @POTUS,” he posted. “Iran is the world’s leading sponsor of terrorism and cannot have nuclear capabilities.”

Both parties have seen splits in recent days over the prospect of striking Iran, including some of Trump’s most ardent supporters who share his criticism of America’s “forever wars.” Republican Rep. Warren Davidson of Ohio posted that “while President Trump’s decision may prove just, it’s hard to conceive a rationale that’s Constitutional.”

Kentucky Rep. Thomas Massie, a longtime opponent of U.S. involvement in foreign wars, also posted on X that “This is not Constitutional.”

“This is not our fight,” said Republican Rep. Marjorie Taylor Greene of Georgia.

Most Democrats have maintained that Congress should have a say, even as presidents in both parties have ignored the legislative branch’s constitutional authority. The Senate was scheduled to vote soon on a resolution from Virginia Sen. Tim Kaine that would require congressional approval before the U.S. declares war on Iran or takes specific military action.

Kaine said the bombings were “horrible judgment.”

“I will push for all senators to vote on whether they are for this third idiotic Middle East war,” Kaine said.

Democratic Rep. Greg Casar, the chairman of the Congressional Progressive Caucus, also called on Congress to immediately pass a war powers resolution. He said politicians had always promised that “new wars in the Middle East would be quick and easy.”

“Then they sent other people’s children to fight and die endlessly,” Casar said. “Enough.”