Free trade reduces the frictions that can arise between nations. Tariffs will only take away stability. President Trump's on-again-off-again tariffs have disrupted the global trading system and caused whiplash for businesses and consumers. He has vacillated mightily, announcing tariffs on imports from practically every U.S. trading partner and then pausing or rolling some back. Legal challenges have added to the turmoil. No matter where the tariffs eventually settle, they will have repercussions that go far beyond trade. Raising tariffs, or at least the constant looming threat of that happening, undermines trade and weakens economic links that stabilise international relations.