Following the killing of Maj. Gen. Qassem Soleimani last week, President Donald Trump on Sunday used Twitter to notify Congress that his administration planned to retaliate, possibly in a “disproportionate manner,” against any military response taken by Iran.

“These Media Posts will serve as notification to the United States Congress that should Iran strike any U.S. person or target, the United States will quickly & fully strike back, & perhaps in a disproportionate manner,” Trump wrote, adding, “Such legal notice is not required, but is given nevertheless!

These Media Posts will serve as notification to the United States Congress that should Iran strike any U.S. person or target, the United States will quickly & fully strike back, & perhaps in a disproportionate manner. Such legal notice is not required, but is given nevertheless! — Donald J. Trump (@realDonaldTrump) January 5, 2020

Similar to the president’s Saturday tweet in which he threatened to commit war crimes by targeting Iranian cultural sites, Trump’s Sunday tweet appeared to violate multiple domestic and international laws in at least four specific ways, according to Yale Law School professor specializing in international law, Prof. Oona A. Hathaway.

“This tweet threatens to break several laws. First, the President cannot notify Congress under the War Powers Resolution by tweet,” Hathaway wrote, referring to the formal notification mandated by the law.

This tweet threatens to break several laws. First, the President cannot notify Congress under the War Powers Resolution by tweet. 1/ https://t.co/tf5m8gXzCh — Oona Hathaway (@oonahathaway) January 5, 2020

Hathaway then explained why Trump’s claim that “legal notice is not required” is objectively false, pointing out that whenever the president involves the armed forces into “hostilities,” he is required to formally notify Congress in writing within 48 hours of the military action.

The international law professor also noted that Trump appears to be ignoring his legally required duty to consult with Congress in advance of introducing U.S. forces to imminent hostilities.

“Third, he is also obligated to ‘in every possible instance . . . consult with Congress before introducing United States Armed Forces into hostilities or into situation where imminent involvement in hostilities is clearly indicated by the circumstances . . .’ under the [War Powers Resolution],” Hathaway continued.

Finally, Hathaway said that Trump’s threat of “disproportionate” retaliation is a promise to violate international law.

Fourth, he is promising a "perhaps … disproportionate" strike in response–that's another promise of an international law violation. Any action taken in self defense (the apparent justification for the strikes) must be necessary and proportionate to the threat posed. 4/ — Oona Hathaway (@oonahathaway) January 5, 2020

“That any of this has to be said suggests just how insane this situation has become,” Hathaway concluded, asking, “Where are the White House, DOJ, DOD, State Dept. lawyers?”

Researcher at the Center for Responsive Politics Anna Massoglia was similarly “dumbfounded” by Trump’s tweet, saying she had pitched just such a scenario for a research project in law school that was rejected as being “too theoretical.”

Dumbfounded. A U.S. President notifying Congress of military action under the War Powers Act on Twitter is *the exact example* I used to pitch researching lack of legal frameworks covering world leaders' social media in law school–but was "too theoretical" https://t.co/PoDdSBmrJL — Anna Massoglia (@annalecta) January 6, 2020

“This is not how legitimate government process works,” national security attorney Mark Zaid said in response to the president’s tweet.

Zaid, who is part of the legal team representing the Ukraine whistleblower whose complaint led to Trump’s impeachment, called on Congress to ensure the proper legal framework is enforced.

“It’s imperative we not concede it can work this way simply because a president is addicted to Twitter. Members of Congress of both parties, this is fundamental issue of separation of powers involving YOUR authority. Step up,” he said.

[Image via Win McNamee/Getty Images]

Have a tip we should know? [email protected]