President Trump seems poised to step up tariffs and trade tensions with China. These tariffs, however, are a major sticking point with all his free trade negotiations — not just with China, but Canada and Mexico too. His recent tweet threatening to increase tariffs on China raises the question: What’s next for the United States–Mexico–Canada Agreement?

Ideally, Trump will keep his promise and scrap all the steel and aluminum tariffs on Canada, Mexico, and other countries (China included). After all, tariffs work just like taxes: They raise barriers to trade and penalize American workers and consumers.