It is a fool’s errand to try to rationalize President Trump’s obsession with tariffs.

This is not to say that people haven’t tried. There are any number of theories that seek to explain Trump’s preoccupation with tariffs and trade wars. Perhaps he wants to revitalize American manufacturing and bring factory jobs back to postindustrial communities wracked by poverty and despair. Perhaps he wants the revenue he generates from large tariffs to reduce deficits and help address the nation’s long-term debt. Or perhaps he hopes to rebalance the global economic system, weakening the dollar in order to make the United States a more export-driven economy.

But each line of thinking shares an obvious problem: How does one accomplish any of these goals with blanket tariffs that threaten to radically reduce trade with the United States? How do you revitalize American manufacturing if manufacturers can’t reasonably import the materials they need to build factories and produce goods? Where is capital supposed to come from? How do you reset the nation’s relationship with its trading partners if those partners are forced to treat you as a bad actor who can’t be trusted? And how are you supposed to revitalize working-class communities if your trade policies will probably destroy as many blue-collar jobs as they might, theoretically, create?