When Donald Trump declared that he'd be imposing tariffs on imported steel and aluminum, it shook markets around the world and prompted many members of his own party to warn that he was liable to set off a trade war. Trump's response? "Trade wars are good."

That gives the impression that the president was making a deliberate, thought-out choice that would get him the result he wanted—in this case, retaliatory tariffs from Canada, which stands to suffer tremendously from Trump's move. But we already know that the decision was made on the spur of the moment, and NBC News points out there were no plans to inform Congress or international trade partners, no pre-planned remarks from the president, and no communications strategy. No one at the Departments of Defense, State, or Treasury knew that this was coming, and the meeting where Trump announced the tariffs never appeared on the president's official schedule, all of which suggests that there wasn't much planning by the White House. And now, NBC News also reports that Trump was actually motivated by something much more erratic than economic concerns: his temper.

A trifecta of events had set him off in a way that two officials said they had not seen before: Hope Hicks' testimony to lawmakers investigating Russia's interference in the 2016 election, conduct by his embattled attorney general and the treatment of his son-in-law by his chief of staff.

Trump, the two officials said, was angry and gunning for a fight, and he chose a trade war, spurred on by Commerce Secretary Wilbur Ross and Peter Navarro, the White House director for trade—and against longstanding advice from his economic chair Gary Cohn and Treasury Secretary Steve Mnuchin.

The word "unglued" comes up in NBC News' reporting from unnamed White House officials, which is usually not a word you expect or want to hear about a president. And as the stock market tumbled in the wake of the his announcement, Trump was said to be "furious," which does not inspire confidence that he'll suddenly start making better policies or at least, you know, sleeping on it before ordering far-reaching economic changes. We should probably just be ready for more impulsive, happiness-chasing decisions whenever someone related to the president is held accountable for once in their life.