U.S. President Donald Trump's tariff decisions since he took office on January 20 have shocked financial markets and sent a wave of uncertainty through the global economy. Here is a timeline of the major developments: February 1 - Trump imposes 25% tariffs on Mexican and most Canadian imports and 10% on goods from China,

The European Union dominates critical pharmaceutical imports into the United States, making the 30% tariffs Trump threatened to go into effect Aug. 1 particularly risky.

President Trump’s trade war continues to cause self-inflicted injuries as American companies are getting slammed by higher fees. This includes General Motors, which revealed tariffs cost them $1.1 billion in the second quarter.