Donald Trump blames Canada for wildfire smoke — but global warming is loading the wildfire dice

A firefighter stands next to burning trees as a wildfire rages outside Bordeaux, France, on July 26, 2026. (AP Photo/Emma Da Silva) Donald Trump blames Canada for wildfire smoke — but global warming is loading the wildfire dice Published: July 28, 2026 12.15pm EDT Share article Print article United States President Donald Trump has accused Canada of “wilful negligence” over wildfires, blaming its forest management, threatening tariffs and floating demands for compensation. His argument is absurd. Smoke does not carry a passport. Wildfires are burning across several countries, causing evacuations and devastating communities. In North America, smoke from fires has spread over many parts of central Canada and the U.S. Wildfires are currently scorching vast areas in Oregon and the Pacific Northwest. France and Spain have evacuated hundreds of thousands of residents as wildfires close in on Bordeaux, France, and grow around Madrid, Spain. Despite Trump’s claims, Canada cannot log, rake or prescribe-burn its way out of a planetary problem. Wildfires require ignition, combustible fuel and weather that permits rapid spread. Climate change does not usually strike the match — people and lightning do that, with lightning responsible for most of the area burned in Canada. But warming weather increasingly determines whether a spark dies or becomes a catastrophe. Hotter air, earlier snowmelt and longer summers mean a drier landscape and more severe fire seasons. In 2004, colleagues and I demonstrated that human-caused climate change had already left a detectable fingerprint on the area burned by Canadian forest fires. A 2024 study found that human influence has made fire seasons like Canada’s record 2023 season more than five times as likely across nearly every Canadian ecozone. Of course, forest management practices matter. Fire suppression, accumulated fuels, vulnerable development and inadequate community protection raise risk in some regions. But many of Canada’s largest fires burn in remote boreal landscapes, and much of the boreal forest is not manageable. Mitigation, not just adaptation Trump’s demand that Canada pay for wildfire smoke is especially galling. The U.S. has emitted more cumulative fossil carbon dioxide than any other country. Trump withdrew the U.S. from the Paris climate agreement while promoting fossil-fuel expansion — worsening the conditions that drive wildfire risk — and now blames a neighbour for the smoke. His supporters should…