Members of the 7th Reconnaissance Squadron prepare to launch an RQ-4 Global Hawk at Naval Air Station Sigonella in Italy in 2018. (Staff Sgt. Ramon A. Adelan/U.S. Air Force/AP) (Staff Sgt. Ramon Adelan/AP)

After President Trump authorized an attack on Iran and then abruptly changed course on Thursday night, Democrats reiterated calls for restraint and demanded congressional oversight of military action.

“Donald Trump promised to bring our troops home. Instead he has pulled out of a deal that was working and instigated another unnecessary conflict,” tweeted Sen. Elizabeth Warren of Massachusetts, a Democratic presidential contender, referring to President Barack Obama’s nuclear agreement that Trump abandoned in 2018. “There is no justification for further escalating this crisis — we need to step back from the brink of war.”

“Only Congress can authorize a war,” Sen. Brian Schatz (D-Hawaii) tweeted. “We should vote next week.”

Democratic leaders had spent much of the day raising similar concerns about the threat of war with Tehran after Iran’s Islamic Revolutionary Guard Corps (IRGC) shot down a U.S. Navy drone. Iran insisted the drone had crossed into its airspace near the Strait of Hormuz, but the U.S. Central Command called it an “unprovoked attack.” Tensions had already spiked over attacks on two tankers in the strait last week. The United States blamed Iran for the attacks — an accusation that Tehran denied.

After Trump invited Democratic leaders to the White House for a bipartisan briefing on the situation on Thursday afternoon, Senate Minority Leader Charles E. Schumer (D-N.Y.) warned that the president “may bumble into a war.”

“One of the best ways to avoid bumbling into war, a war that nobody wants, is to have a robust open debate and for Congress to have a real say,” Schumer said. “We learned that lesson in the run-up to Iraq."

House Speaker Nancy Pelosi (D-Calif.) said that “we must do everything we can not to escalate the situation, but also to make sure that our personnel in the region are safe.”

After first calling the drone shoot-down a “very big mistake,” Trump himself sounded a note of caution, telling reporters at the White House that top Iranian officials may not have signed off on the actions of the IRGC, which his administration has classified as a terrorist group. “I find it hard to believe it was intentional,” he said, referring to the decision-making of Iranian leaders.

But by Thursday evening, U.S. military forces on Trump’s authorization moved to launch a counterstrike in retaliation for the shoot-down, reported The Washington Post’s Missy Ryan, Erin Cunningham and Dan Lamothe. Hours before that attack was scheduled to begin, though, Trump changed his mind and aborted the operation.

Some Democrats argued that the quick change of course suggested that Trump had backed himself into a corner by pulling out of the 2015 nuclear deal between Iran and six world powers, including the United States, in May 2018. Trump has called the agreement “insane” and “an embarrassment.”

“The place we have arrived at tonight on Iran is Donald Trump’s choice,” Sen. Chris Murphy (D-Conn.) tweeted. “He chose escalation over diplomacy, without any idea how to get out of the downward spiral he set in motion.”

Other Democrats noted that, according to both U.S. officials and European allies, Tehran had been abiding by the nuclear deal until Trump walked away and imposed new economic sanctions.

“Iran was complying with the nuclear deal when he pulled out over the objections of anyone who knows anything about the Middle East or nuclear issues,” Schatz tweeted, pointing the finger at both the president and his national security adviser. “This is a crisis made by Donald Trump. And John Bolton.”

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