Can Trump order a military strike on Iran without Congressional Approval? It depends who you ask

Although some Democratic and Republican lawmakers agree there should be some degree of "measured response" to Iran's recent alleged aggression toward U.S. assets abroad, there is far less agreement when it comes to whether President Donald Trump could unilaterally take military action against the Middle Eastern nation without congressional approval.

Generally, Democrats tend to argue that Trump would need to seek authorization from Congress to initiate certain military operations against a foreign adversary. Many Republicans, on the other hand, point to past precedent and laws that suggest that — short of declaring war — the commander-in-chief has the authority to take action on his own.

Tensions have heightened between the U.S. and Iran following a string of actions allegedly taken by Iran on U.S. assets abroad, including rocket attacks against a military base in Iraq housing U.S. troops and an attack on two oil tankers in the Gulf of Oman. Then, on Thursday, Iran shot down a U.S. Navy drone, prompting Trump to plan military strikes against Iranian targets, only to a later scrap the attack shortly before it was set to begin.

The War Powers Resolution of 1973 gives a president 60 days to obtain congressional approval after making foreign military strikes and informing Congress "within 48 hours." Otherwise, he then has another 30 days to cease the operations. Under these conditions, Yale Law School Professor Bruce Ackerman told Newsweek, Trump's clock has run out.

"More than 60 days have elapsed since the President first began to engage in acts of 'hostilities' against Iran, as the term is defined by the War Powers Resolution of 1973—both through his deployment of US forces and his support of Saudi military actions against Iran in connection with the military struggle between Tehran and Riyadh in Yemen," said Ackerman.

The Authorization for Use of Military Force (AUMF), passed a week after the 9/11 terrorist attacks in 2001, allowed the president to "use all necessary and appropriate force" against those involved in the attacks. Since then, presidents have used the Bush-era law to justify military action in the Middle East.

Can Trump strike Iran without Congressional Approval
President Donald Trump speaks to the media prior to departing on Marine One from the South Lawn of the White House in Washington, DC, on May 20 as he travels to Pennsylvania for a campaign rally. SAUL LOEB/AFP/Getty

"I don't think he has any current authorization," said Representative David Cicilline, a Democrat on the House Foreign Affairs Committee. He acknowledged that some may argue the recent alleged aggression by Iran could be viewed as "an attack on the United States that would warrant a justification of a military strike without congressional authorization."

"It certainly doesn't excuse consultation with Congress," Cicilline continued. "The most important response is to deescalate the situation."

Speaker of the House Nancy Pelosi said she was not advised in advance by the White House of the planned military operation against Iran, breaking with precedent.

"I did not receive any heads-up that there was a strike that was in the works," she told reporters Friday. "Maybe the other leaders did, on the Republican side, but I did not receive any of that. And that would be a departure—the President has informed us, for example, in Syria, before we went in."

In a recent briefing to top congressional leaders from administration officials, Pelosi added that Democrats from both chambers "were very clear that Congress must act—that they must have the authority of Congress, before we initiate military hostilities into Iran."

However, Republicans don't quite see it that way. They point to the AUMF and the War Powers Resolution as laws that provide the president additional executive powers when it comes to issuing foreign military strikes.

"We don't have 435 commanders-in-chief out here," Representative Adam Kinzinger told Newsweek. Although the Foreign Affairs Committee member and veteran is an ally of the president's, he wasn't afraid to offer up harsh criticism for Trump's handling of Iran, arguing his reversal on the military strikes "undercuts" U.S. strategy.

Still, Kinzinger believed Trump does not need Congress to approve military strikes in the region, and he believed the administration has done well keeping members in the loop.

"Our job is to declare a state of war exists and funded, it's not to make every military move and decision. So, no, I don't think it needs to [seek congressional approval]," he said. "If it's not military or something, there's got to be a cost to Iran—we have to send a message."

Fellow Foreign Affairs Committee Republican Steve Chabot believed that short of declaring war, the administration was well within its right to take action. Based on "tradition in recent decades" under AUMF and War Powers, the Ohio lawmaker said Trump is authorized.

"I do think there's a congressional role—certainly, obviously—if we declare war, but I don't anticipate that that's something on the horizon," he told Newsweek.

He, like other members on both sides of the aisle, did express a willingness to update the AUMF to limit presidential authority. Through an appropriations package Wednesday, the majority-Democrat House voted to repeal the law—but it is unlikely the Republican-controlled Senate would also pass this measure.

"The [AUMF] is pretty outdated when you consider it's basically almost two decades old now," Chabot said. "But let's face it, you know, we're going to get a majority vote here and, and, you know, 60 votes over in the Senate is very challenging for, for anything, even something that ought to be low hanging fruit like infrastructure."