House Speaker Nancy Pelosi (D-Calif.) speaks during a bill enrollment ceremony for the Taxpayer First Act on Capitol Hill in Washington D.C., U.S. on Friday. (Stefani Reynolds/Bloomberg)

President Trump’s decision to abort a planned retaliatory attack on Iran was met with a wave of relief Friday from Republicans and Democrats weary from nearly two decades of American military entanglement in the Middle East.

That relief came, to a degree, from across the political spectrum: It included top Democratic leaders — House Speaker Nancy Pelosi (D-Calif.) said a deadly strike “would be very provocative” — and also encompassed some hard-right Trump allies and hard-left Democrats who share concerns over escalating foreign military commitments.

“I believe it’s prudent to make sure you got it right, you have the best intelligence that is available, and you’ve taken the proper amount of time to consider all the ramifications of what you do,” said Rep. Mo Brooks (R-Ala.), a member of the House Armed Services Committee and the conservative House Freedom Caucus.

“Deciding not to strike was the right decision,” said Rep. Alexandria Ocasio-Cortez (D-N.Y.), adding that Democrats ought to give Trump “encouragement” to step from the brink of conflict.

The strange-bedfellows reaction to Trump’s decision underscores how difficult it could be for the Trump administration to build support in Congress for any kind of sustained military campaign in Iran. Although the president has unquestioned constitutional power to respond to an attack on U.S. forces, there are bipartisan calls to ensure congressional assent for a more protracted campaign abroad.

The aborted strike also thrust top Democrats into the somewhat unusual position of praising Trump after spending more than two years lambasting his Iran policy, which has included canceling the nuclear deal negotiated by former president Barack Obama and proceeding with a “maximum pressure” sanctions campaign that brought tensions, by Trump’s account, within a half-hour of a shooting war Thursday night.

“He certainly deserves praise for not doing something that would have been, I think, unwarranted and unjustified,” said House Majority Leader Steny H. Hoyer (D-Md.). “He does not deserve praise for the lack of consistency of his policies and the instability that that creates.”

Trump faced more pointed criticism, in fact, from fellow Republicans — particularly those more squarely in the traditional school of GOP foreign policy, who argued that American credibility was on the line after Iran allegedly mined allies’ oil tankers and downed a surveillance drone costing upward of $180 million.

“Weakness is provocative,” Rep. Liz Cheney (R-Wyo.), the House Republican Conference chairwoman and daughter of former vice president Richard B. Cheney, said on the Hugh Hewitt radio show Friday. “If Iran thinks that it can demonstrate to the world that somehow it’s able to take advantage of the United States, that it’s able to attack and destroy one of our drones without any consequence or with the only consequence being that we now ask to speak to them, I think that that’s very dangerous.”

Several Republicans compared Trump’s reticence to strike Iran with Obama’s unwillingness to order strikes against Syria in 2013 after President Bashar al-Assad appeared to violate the “red line” Obama had declared by using chemical weapons in the early stages of the country’s devastating civil war. Although the United States avoided another costly foreign military excursion, Obama’s critics blamed his decision for paving the way for the ensuing humanitarian morass and rise of the Islamic State terror group.

If Trump does not respond forcefully to Iran’s targeting of the drone, said Rep. Adam Kinzinger (R-Ill.), a member of the House Foreign Affairs Committee, “it’s definitely a hit to the credibility” of the United States.

“You can’t, on the one hand, have condemned, as many of us did, President Obama walking back the 2013 strike and then judge [Trump] by a much different standard,” he said.

But other Republicans, including some heretofore outspoken Iran hawks, are praising Trump, or at least giving him the benefit of the doubt. And some acknowledge there is a limited appetite — after nearly two decades of unceasing conflict in Afghanistan, Iraq and Syria — among the American public and U.S. allies for a new war in the Middle East.

Rep. Lee Zeldin (R-N.Y.), a Foreign Affairs Committee member and fierce critic of the Iran nuclear deal, said Trump was justified in considering the proportionality of a military response to Iran’s provocation.

“I know that the president doesn’t want military conflict with Iran. I don’t believe our country wants military conflict with Iran. I don’t want military conflict with Iran,” he said, adding: “I will say that at times, with the way Iran has been acting out, it seems like they may start begging for it.”

Senate Foreign Relations Committee Chairman James E. Risch (R-Idaho) told reporters Friday that Trump “struggled” with his decision before concluding that a potentially deadly attack on Iran was not justified by the downing of an unmanned drone.

“I think patience is appropriate,” he said, provided the Trump administration retaliates against Iran in the coming days with “nonkinetic” — that is, nondeadly — options. Risch said he would be “very surprised” if the administration didn’t pursue such a response.

In Congress, the looming battle for lawmakers will be to assert constitutional warmaking powers as the sabers continue to rattle. In both the House and Senate, Democrats are seeking to amend pending defense authorization legislation to assert that Trump has no legal right to engage in ongoing military hostilities in Iran without seeking congressional approval. Those efforts have some bipartisan support, and they could come to a head as soon as next week, when the Senate begins debating the defense bill.

“President Trump ran as a very different kind of Republican, somebody who wanted to end wars, not start them, and I think he is utilizing appropriate caution,” said Rep. Matt Gaetz (R-Fla.), who is co-sponsoring the amendment in the House with Rep. Ro Khanna (D-Calif.).

House Democrats this week passed a funding bill that explicitly canceled presidential warmaking authority dating to the Sept. 11, 2001, terrorist attacks, though that language is unlikely to become law in the near term.

“We as Democrats are saying to the president that we absolutely intend to do our job, and if he is considering the use of force, he has to come to us,” said Rep. Barbara Lee (D-Calif.), who successfully pressed for the inclusion of the language.

Pelosi on Friday repeated that Democrats believe that Trump must have congressional assent before the United States “initiates military hostilities” in Iran. She said she did not hear from Trump or his aides Thursday that a strike was imminent, and she said upon leaving the Capitol for the weekend that she had not spoken to Trump about the matter since visiting the White House for a briefing Thursday afternoon.

“A strike of that amount of collateral damage would be very provocative, and I’m glad the president did not take that,” she said, adding: “De-escalate, de-escalate, de-escalate. Take a deep breath and de-escalate.”

Colby Itkowitz contributed to this report.