But it reflects concern in Europe over the possible impact of new American tariffs, notably on steel. The United States is the world’s largest importer of steel, and while many of Mr. Trump’s arguments have focused on cheap steel from countries like China, the European Union as a whole is the single biggest exporter of steel to the United States. At the same time, the region is concerned that cheap steel that had been destined for the United States could now flood the Continent, putting significant pressure on European producers.

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While retaliation from Brussels appears limited for now, it could have an impact on American domestic politics. Bourbon, one of the products that European officials have targeted, is made in Kentucky, the home state of Mitch McConnell, the Senate majority leader. Other items that could face tariffs are motorcycles, and the corporate headquarters of Harley-Davidson are in Wisconsin, Mr. Ryan’s state.

“The Europeans have rights, too, to retaliate,” said Peter Chase, a former American diplomat who is now a senior fellow at the German Marshall Fund in Brussels focusing on trade. “The E.U. is concerned that behind it all, there are people in the U.S. administration that don’t care that there might be damage to the international system of rule of law that we have created.”

The list, which was leaked on Monday and has been referred to by the European Commission president, Jean-Claude Juncker, is subject to the agreement of the bloc’s 28 member states.

It highlights how sharply the outlook on trade between the United States and Europe has shifted. Since 2013, Washington and Brussels have been negotiating a vast trade deal, known as the Trans-Atlantic Trade and Investment Partnership.

By late 2016, however, those talks appeared to have reached a stalemate, and Mr. Trump’s withdrawal from a similar pact with Pacific Rim countries early in his presidency signaled the death of the European agreement, as well.

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The strong negative reaction to Mr. Trump’s planned tariffs appears to have had little impact on the president, who insisted this week that he would not back down.

On Tuesday, Mr. Trump singled out the European Union, which he said had “not treated us very well, and it’s been a very, very unfair trade situation.” The president warned that the United States would also consider raising its tariffs on cars made within the bloc if the European Union were to retaliate.

While he left the door open for compromise with allies, tensions are rising in Europe.

“We’ve loaded the guns,” said Charles de Lusignan, a spokesman for the European Steel Association, a lobbying group, “and we’re ready to use them in case the aggression comes.”