The June 29 truce in the trade war between the United States and China lasted just over one month. Thirty-three days after the presidents of the two countries met in Osaka, Japan, and agreed to resume negotiations, President Trump, frustrated by the slow progress of negotiations, announced that the U.S. would impose a 10% tariff on an additional $300 billion worth of Chinese imports on September 1. The financial markets were rocked by the sudden reversal, and analysts wondered: “What triggered Trump’s announcement?”