North America isn't getting along anymore. Canada's Prime Minister is having testy phone calls with President Trump about the War of 1812. Mexico has slapped the United States with a $3 billion dollar tax bill. It all comes down to steel. Today, U.S. senators from both aisles announced new attempts to curb the president's tariffs power. Vox’s Matthew Yglesias explains how steel sparked a trade war. Learn more about your ad choices. Visit podcastchoices.com/adchoices