WASHINGTON ― The U.S. House approved a bipartisan, Senate-passed measure Wednesday aimed at limiting President Donald Trump’s authority to launch military operations against Iran.

The White House issued a threat Tuesday that Trump will veto the measure, warning it would “undermine the ability of the United States to protect American citizens whom Iran continues to seek to harm.”

The measure was under House floor consideration as U.S. officials confirmed two Americans and one British national were killed when more than 15 small rockets hit Camp Taji in Iraq. Officials did not say what group they believe launched the rocket attack, but Kata-ib Hezbollah or another Iranian-backed Shia militia group is likely.

The resolution passed the House 227-186 and the Senate 55-45. On Wednesday, six House Republicans and one independent joined Democrats to constrain the White House, with six Democrats defecting.

To override an expected Trump veto, two-thirds votes in the House and GOP-run Senate would be needed.

Donald Trump

Authored by Sen. Tim Kaine, D-Va., the resolution says Trump must win approval from Congress before engaging in further military action against Iran. House Majority Leader Steny Hoyer, D-Md., said the measure was not about Trump, but about asserting Congress’ powers under the Constitution to declare war.

“There are a lot of countries where one person makes decisions. They’re called dictators. Our Founding Fathers did not want dictators running the United States of America,” Hoyer said.

Congressional Democrats have also been sharply critical of the administration’s shifting justification for its Jan. 3 drone strike against Iranian Gen. Qassem Soleimani, to which the rocket barrage was in response. They have criticized the effectiveness of the administration’s “maximum pressure” campaign against Iran, arguing that Tehran immediately replaced Soleimani with his deputy and that the country is still enriching nuclear material.

“We’re now closer to a war with a country that’s closer to possessing a nuclear weapon," House Foreign Affairs Committee Chairman Eliot Engel, D-N.Y., said in a House floor speech. “The last few weeks have also shown the administration’s scrambling to come up with a legal justification for the strike.

"Contrary to the initial claims, it quickly became clear that there was no imminent threat. In fact, when the administration sent a legally required report to Congress laying out the legal and policy justifications, there was no mention of an imminent threat, none whatsoever.”

The White House veto threat issued Tuesday argued that the measure was unnecessary because “there have been no further uses of force between Iran and the United States” since Iran’s Jan. 8 missile strike against U.S. forces in Iraq in retaliation for Soleimani’s death.

House Foreign Affairs Committee ranking member Michael McCaul, R-Texas, echoed those arguments.

“If we were to launch strikes in Iran, I believe the president would need to come before this body to ask for a new authorization, but that is not what we are facing,” McCaul said, adding that Trump has said he does not want to go to war against Iran and has shown restraint in taking military action.

Eliot Engel,Michael McCaul

The administration and allies have argued the Dec. 27 killing of an American interpreter in Iraq by Iranian-backed militias and the Dec. 31 attack on the U.S. Embassy in Baghdad by supporters of an Iranian-backed militia were part of a pattern that would have escalated without Soleimani’s death.

According to the White House memo that recommends a veto, the U.S. strike was a justified response “to an escalating series of attacks in recent months by Iran and Iran-backed militias on United States forces and interests in the Middle East.”

The memo also argued that Trump was authorized by his executive powers as well as the 2002 war authorization, which ― beyond its initial focus on former Iraqi leader Saddam Hussein and his forces ― justified actions to stabilize Iraq, defend U.S. troops and respond to threats from Iran-backed militias.

In his House floor speech, Engel refuted the White House’s position as an overly expansive interpretation of the law that’s both out of step with Congress and the American public.

“I’m worried that the president made a decision to escalate tensions with Iran, failed to consult Congress, misled the American people why the strike was necessary, then switched gears and conjured up this dubious legal justification,” Engel said. “The American people don’t want war with Iran. Congress has not authorized war with Iran. That should be crystal clear.”

The Associated Press contributed to this report.

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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