President Trump followed through Thursday with his threat to impose tariffs of up to 25 percent on steel and aluminum from the European Union, Canada, and Mexico. In late April, Trump delayed the tariffs until June 1 to allow space for trade negotiations, which proved fruitless. Mexico immediately responded with tariffs on American grapes, apples, and other products, and Europe declared this "a bad day for world trade," vowing to impose retaliatory duties on U.S. goods.

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