Canada can huff, and puff, but if anything’s going to blow down Trump’s house of tariffs it’s going to be the reaction within the US. And there are signs of pushback. The stock market is turning, economic sentiment is nosediving, the U.S. president’s approval is receding, and American lawyers are preparing lawsuits. Those factors will likely pack more punch in Washington than the $155 billion in counter-tariffs threatened by Canada. …Markets replied by quickly wiping out their entire gains for 2025, with the S&P 500 losing 1.76% on the day, triggering hundreds of billions in losses. …But that modest single-day decline is by no means the only grey cloud on the economic horizon. US consumer confidence has had its sharpest monthly drop since the pandemic. …So now we watch the Americans investors and the courts. For all the talk about how Canada might fight tariffs, the decisive battle is south of the border.