President Donald Trump imposed the steepest American tariffs in a century, stepping up his campaign to reshape the global economy and unnerving investors who see a trade war as a risk to US growth.

President Trump is preparing to announce another big round of tariffs Wednesday. He argues that import taxes help to protect U.S. producers from foreign competition.

Trading partners are expected to respond with countermeasures of their own that could lead to dramatically higher prices for everything from bicycles to wine.