U.S. President Donald Trump broadened his global trade war on Tuesday as he announced a 50% tariff on imported copper and said long-threatened levies on semiconductors and pharmaceuticals were coming soon.

U.S. trading partners are weighing responses after President Donald Trump’s latest action on tariffs sparked a stock market selloff Monday. The White House sent letters yesterday to about a dozen countries laying out the rates at which imports would be taxed—ranging from 25% to 40%—if no other trade agreements are reached.

President Donald Trump announced on Monday that he is levying tariffs against South Korea and Japan beginning in August. Trump