President Donald Trump's threat of tariffs on goods from Mexico, Canada and China is aimed at stopping the flow of fentanyl into the U.S.

Donald Trump’s short-lived feud with Mexico’s president is settled after she pledges to stop fentanyl flowing into the United States.

President Donald Trump has slapped tariffs on Chinese goods, accusing Beijing of allowing fentanyl and precursor chemicals to be shipped to the United States.

China's government on Sunday denounced the Trump administration's imposition of a long-threatened 10% tariff on Chinese imports while leaving the door open for talks with the U.S. that could avoid a deepening conflict.

The White House says fentanyl smuggled to the U.S. justifies tariffs against Canada, China and Mexico. But fentanyl deaths and smuggling have been dropping fast — and Canada plays almost no role.