For the second time this week, President Trump has threatened to disrupt trade with a close ally for retaliating in a trade war that he started — a tactic that could lead to compromise, or to economic spats that spiral further out of control.

On Thursday morning, Mr. Trump tried to cow the European Union into submission, threatening in a social media post to put a 200 percent tariff on European wine and Champagne unless the bloc dropped a 50 percent tariff on U.S. whiskey. The European Union had imposed that tariff in response to levies that Mr. Trump put on global steel and aluminum on Wednesday.

Mr. Trump deployed a similar tactic against Canada on Tuesday, threatening to double 25 percent tariffs on Canadian steel and aluminum to try to get Ontario to lift a surcharge on electricity sold to the United States. The province had imposed the charge after Mr. Trump put other tariffs on Canada this month.

After Ontario suspended its surcharge, Mr. Trump walked back his threats.

Over the last several weeks, Mr. Trump has presided over a confusing and potentially economically devastating back and forth of tariffs and tariff threats, playing a global game of chicken as he tries to get some of the United States’ closest allies and trading partners to back down.

Mr. Trump has wielded the tariff threats without regard for their economic consequences and, increasingly, seemingly without regard for the impact on stock markets. The S&P 500 slumped again on Thursday after Mr. Trump threatened Europe and reiterated at the White House that he would impose big tariffs.

When asked whether he might relent on Canada, which sent a delegation to the United States on Thursday to try to calm trade tensions, Mr. Trump said: “I’m not going to bend at all.”

He said the United States didn’t need imports like lumber and energy from Canada, one of America’s largest trading partners. “We don’t need anything they have,” he said.

The president, who spoke to reporters during a meeting with Mark Rutte, the secretary general of the North Atlantic Treaty Organization, acknowledged that his tariffs could cause “a little disruption” but said that “it won’t be very long.”

“And we have to do this,” he said. “I’m sorry, we have to do this.”

Treasury Secretary Scott Bessent, asked on Thursday about market volatility and the economic effects of tariffs, said the White House was not concerned “about the short term.”

“We’ve got strategic industries we’ve got to have,” Mr. Bessent said. “We want to protect the American worker.”

Commerce Secretary Howard Lutnick also warned other countries against retaliating against the United States, saying in an interview on Bloomberg TV on Thursday that Mr. Trump could respond temperamentally.

“If you make him unhappy, he responds unhappy,” Mr. Lutnick said.

Mr. Lutnick said some countries, like Britain and Mexico, had thoughtfully examined how they did business with the United States. But for countries that respond with further tariffs, “the president’s going to deal with them with strength and with power,” he threatened.

It remains to be seen whether other countries will retaliate with their own levies and, if so, how many economic disagreements may spiral into true tit-for-tat trade wars. Mr. Trump has promised more levies on cars and other products to come in April.

Some governments, like those in Australia, Brazil, Britain, Japan and Mexico, have chosen not to retaliate for now, as they try other routes to defuse tensions with Mr. Trump. But China, the European Union and Canada have all made different calculations.

Those governments may be encouraged by domestic political constituencies to stand up to Mr. Trump’s bullying or, in the case of Europe and China, emboldened by the size of their economies.

Some European officials said they wouldn’t bow to pressure. In a statement on Wednesday, Ursula von der Leyen, the president of the European Commission, the bloc’s executive arm, said that Europe needed to act to “protect consumers and business” and that it would take “strong but proportionate” countermeasures.

“We will not give in to threats,” Laurent Saint-Martin, France’s foreign trade minister, said in a post on X. Mr. Trump “is escalating the trade war he chose to unleash,” he added.

Canadian officials have also generally been outspoken against the United States, a dynamic that may be amplified by a political transition and an upcoming federal election in Canada.

“If you hit us, we will hit back,” Chrystia Freeland, a former Canadian minister of finance, said in an interview on CNN on Thursday. Ms. Freeland said that Canada was small but that it had leverage in the economic relationship because it was the largest export market for the United States by far.

“Canada is a more important export market for the U.S. than China, Japan, the U.K. and France combined,” she said. “You guys are the country that invented the phrase ‘the customer is always right.’ Well, we’re your biggest customer.”

Mr. Trump may be gambling on the idea that other countries are more dependent on the U.S. market than the United States is on them. Canada sends about 80 percent of its exports to the United States, while roughly 17 percent of U.S. exports go to Canada.

But being larger and more distant, the European Union and China are less reliant on American buyers. The United States is the destination for about 20 percent of E.U. exports and about 15 percent of Chinese exports.

On Thursday, Canada initiated a dispute at the World Trade Organization over the steel and aluminum tariffs that Mr. Trump had imposed the day before. China initiated a suit over a separate tranche of tariffs last month. But the W.T.O. challenges are largely a symbolic gesture, since the United States disabled the organization’s dispute settlement system in Mr. Trump’s first term.

Canadian officials were expected to meet with Mr. Lutnick to discuss trade issues on Thursday. A European spokesman said Maros Sefcovic, the European Union’s trade commissioner, would talk with both Mr. Lutnick and Jamieson Greer, the U.S. trade representative, on Friday.

Jeanna Smialek and Matina Stevis-Gridneff contributed reporting.