The Trump administration has made a habit of lying about all things related to Iran, so it should come as no surprise that their official justification for killing Soleimani is similarly dishonest. Pompeo has said that the assassination was ordered to prevent an “imminent” attack, but that appears to be based on nothing:

1. I’ve had a chance to check in with sources, including two US officials who had intelligence briefings after the strike on Suleimani. Here is what I’ve learned. According to them, the evidence suggesting there was to be an imminent attack on American targets is “razor thin”. — Rukmini Callimachi (@rcallimachi) January 4, 2020

To top it off, the vice president went on Twitter to spread a damnable lie in an attempt to tie Soleimani and Iran to the 9/11 attacks:

Then Vice President Mike Pence falsely suggested Iran was behind 9/11. Pence tweeted that Soleimani and his Quds Force “assisted in the clandestine travel to Afghanistan of 10 of the 12 terrorists who carried out the September 11 terrorist attacks in the United States.” Not only were there 19 attackers, but an incredulous ex-CIA counterterrorism analyst wearily noted that it “sounds like he’s directly tying Soleimani to 9/11.” The 9/11 Commission, as a different ex-CIA analyst tweeted, found that Iran had no advance knowledge of the attacks.

The administration feels compelled to lie about an “imminent” attack because if that isn’t true they don’t have a leg to stand on legally or otherwise for taking such a drastic and dangerous action. If there wasn’t an “imminent” attack in the works, the assassination can’t be spun as a “defensive action” at all, and the president has no authority to initiate hostilities against another state like this. The lack of an “imminent” threat isn’t just a matter of the administration deceiving the public about why they took this action, but it also shows that the attack was both illegal and unjustifiable. The idea that the 2002 Iraq war AUMF somehow covers initiating hostilities against Iran in 2020 is ludicrous and shouldn’t be taken seriously.

Ryan Costello comments on the administration’s lies:

Add it all up, and you have an administration that ignored Congress while planning an assassination of a foreign general that risks a disastrous war without any plausible argument that doing so was authorized by Congress. This is an administration that has lied over matters big and small, and thinks it can get away with lying Americans into war while repeating the George W. Bush playbook that led to the 2003 invasion of Iraq. Hence, the warnings of an imminent terror threat that doesn’t appear to have existed as well as the bizarre lie from Vice President Mike Pence attempting to link Soleimani to the September 11 attacks. And, just like the George W. Bush administration had delusions about what would come after the invasion of Iraq, many members of Trump’s team are apparently deluded about what comes next. As one senior State Department official claimed, they don’t expect additional retaliation from Iran because the U.S. is “speaking in a language the regime understands.”

The decision to assassinate Soleimani appears to have been as abrupt and arbitrary as many other Trump decisions. The Los Angeles Timesreports:

One briefing slide shown to Trump listed several follow-up steps the U.S. could take, among them targeting Suleimani, the head of the Islamic Revolutionary Guard Corps’ elite Quds Force, according to a senior U.S. official familiar with the discussions who was not authorized to talk about the meeting on the record. Unexpectedly, Trump chose that option, the official said, adding that the president’s decision was spurred on in part by Iran hawks among his advisors.

One reason that the president ordered the attack seems to be the fear of appearing weak:

Trump was also motivated to act by what he felt was negative coverage after his 2019 decision to call off the airstrike after Iran downed the U.S. surveillance drone, officials said. Trump was also frustrated that the details of his internal deliberations had leaked out and felt he looked weak, the officials said.

The president made a terrible decision that puts more Americans at risk in part because of his own insecurity and vanity, and he ordered the military to commit an act of war against another state without any legal justification. Congress and the public need to make it absolutely clear that we reject war with Iran. The first thing Congress can do is to approve Sen. Kaine’s war powers challenge to the administration. The president has recklessly led the U.S. into an unnecessary conflict, but there is still a chance to halt it before more lives are lost.