President Trump has continued to announce tariffs against Canada, despite the fact that the Supreme Court may be on the verge of taking away his power to do so.

Last week, Trump threatened to impose 100% tariffs on Canadian imports as a result of Canada’s potential trade deal with China.  Then, today, he announced a 50% tariff on any and all Canadian aircraft sold in the US due to his claim that Canada is unfairly failing to certify aircraft made by the US company Gulfstream.

These action come on the heels of Canadian Prime Minister Mark Carney’s speech in Davos, Switzerland that was highly critical of Trump’s disruption of the world economic order.  Carney received a standing ovation, in contrast to the icy reception Trump received from his Davos speech.  Reports are that this has resulted in Canada, previously our closest ally, being the most recent preferred target of Trump’s rage.

However, any day now, the Supreme Court may issue its opinion in Learning Resources v. Trump, which could invalidate all of Trump’s tariffs that were imposed by it under the International Emergency Economic Powers Act (IEEPA).  This decision could disarm Trump of his most frequently used weapon against US trading partners, including close allies like Canada and Europe.  The decision could force the US government to issue massive refunds to importers who have paid tens of billions of dollars in tariffs to date.  If Trump wants to impose tariffs in the future, he will need to use other provisions of US law, which are much more restrictive on the reasons tariffs can be imposed, and the length of time they can be in place.

Based on the oral argument in the Learning Resources case, many legal observers expect that Trump will lose, with the court ruling that the IEEPA tariffs are unconstitutional.  This result will be exceedingly embarrassing to Trump, who has used tariffs as the cornerstone of both his economic and foreign policies.  But Trump appears to be clueless about the impending confiscation of his preferred armament.  Instead, he continues with his bellicose rhetoric and wrecking ball tactics, doing serious and lasting damage to the country’s standing in the world. 

What will Trump do when he finds himself disarmed in the trade war he started?  Will the rest of the world be further emboldened to challenge Trump when his ability to retaliate has been compromised?