Trump threatens to add Canadian wildfire smoke costs to tariffs, legal mechanism unclear

President Trump on Friday directed blame at Canada for wildfire smoke blanketing parts of the United States, writing on Truth Social that the country had refused to engage in "basic Forest Management and Debris Removal" and that this constituted "Willful Negligence." He wrote that the cost of the pollution "must of necessity be added to the TARIFFS Canada is currently paying" and said he would call Prime Minister Mark Carney later in the day.

According to Fox News, smoke from nearly 850 active wildfires across Canada — including more than 180 in Ontario — has drifted into the United States, prompting air quality alerts in more than 20 states from the Upper Midwest to the Northeast, according to NASA. Fox News also included commentary from a cardiothoracic surgeon advising residents, particularly the elderly, young children, and pregnant women, to stay indoors and use N95 masks.

The White House did not respond to questions about which law would authorize the tariffs. Spokesman Kush Desai said in a statement, as reported by The Washington Post, that the president has "numerous tariff powers at his disposal" but declined to address how any rate would be calculated given Trump's description of the costs as "incalculable."