Trump invokes IEEPA to impose 25% tariffs on Canada and Mexico, triggering WTO and USMCA disputes

President Trump invoked the International Emergency Economic Powers Act to impose 25 percent tariffs on all Canadian and Mexican goods, citing the flow of fentanyl across both borders as an "unusual and extraordinary threat." Canada and Mexico immediately filed dispute cases under the United States-Mexico-Canada Agreement and at the WTO. Federal courts in New York and Washington received emergency challenges arguing IEEPA did not authorize tariffs — a legal question the Supreme Court had never directly resolved.