The Trump administration’s legal justification for the Soleimani assassination is as preposterous as you would expect it to be:

The White House delivered its legal justification for the January airstrike that killed Iranian General Qassem Soleimani, arguing that President Donald Trump was authorized to take the action under the Constitution and 2002 legislation authorizing the Iraq war.

The administration is no longer pretending that the assassination had anything to do with stopping an “imminent” attack. They no longer claim that this is why the assassination was ordered. That by itself is a remarkable admission of the illegality of the strike. If there was no “imminent” attack, the U.S. was taking aggressive action against a high-ranking official from another country. There is no plausible case to be made that this was an act of self-defense. Not only did the president lack the authority to do this on his own, but it would have been illegal under international law even if he had received approval from Congress before doing it. The administration spent weeks hiding behind the “imminent” attack lie because without it there was no justification for what they did.

Abandoning the “imminent” attack claim also means that the administration is trying to lower the bar for carrying out future strikes against Iran and its proxies. Ryan Goodman points this out in his analysis of the administration’s statements:

The absence of an imminent threat is relevant not only to the legal and policy basis for the strike on Jan. 2. It is also relevant for potential future military action. The administration’s position appears to boil down to an assertion that it can use military force against Iran without going to Congress even if responding to a threat from Iran that is not urgent or otherwise imminent.

In short, Trump and his officials want to make it easier for them to commit acts of war against both Iran and Iraqi militias.

Trying to distort the 2002 Iraq war AUMF to cover the assassination of an Iranian official just because he happened to be in Iraq at the time is ridiculous. Congress passed the disgraceful 2002 AUMF to give George W. Bush approval to attack and overthrow the Iraqi government. That did not and does not give later presidents carte blanche to use force in Iraq in perpetuity whenever they feel like it. The fact that they are resorting to such an obviously absurd argument shows that they know they don’t have a leg to stand on. The Soleimani strike was illegal and unconstitutional, and there is not really any question about it. The administration’s own justification condemns them.

The president’s lawlessness in matters of war underscores why it is necessary for Congress to reassert its proper constitutional role. The Senate passed S.J.Res. 68, the Tim Kaine-sponsored war powers resolution, by a vote of 55-45 to make clear that the president does not have authorization for any further military action against Iran:

In a bipartisan rebuke of President Trump on Thursday, a Senate majority voted 55 to 45 to block the president from taking further military action against Iran — unless first authorized by Congress. Eight GOP senators joined every Democrat to protest the president’s decision to kill a top Iranian commander without complying with the War Powers Resolution of 1973.

The president has already said that he will veto the resolution, just as he vetoed the antiwar Yemen resolution last year. He is proving once again beyond a shadow of a doubt that he has no respect for the Constitution or Congress’ role in matters of war.