LONDON — Bo Albertus, a school principal in Denmark, finds the Spanish raisins he now snacks on less tasty than his favorite Sun-Maid ones from California. There is no perfect substitute for Heinz tomato soup, a staple in his pantry. And he misses Pepsi Max.

But as long as President Donald Trump pursues policies that Albertus, 57, believes put Europe’s economy and security at risk, he will boycott these and other U.S. products.

He is one of a growing number of Europeans, Canadians and others who are forgoing U.S. goods to show their anguish and dismay at Trump’s treatment of longtime allies.

“I felt a sense of powerlessness,” said Albertus, who is an administrator of a Danish Facebook group dedicated to boycotting U.S. goods that has 90,000 members. “We all feel that we are doing something. We are acting on our frustration.”

The strongest momentum behind such consumer action appears to be in countries that Trump has directly antagonized, like Denmark, whose territory of Greenland he has threatened to take, and Canada, which he has repeatedly said should become America’s 51st state.

But as Trump embraces Russian President Vladimir Putin and imposes tariffs on European goods, groups dedicated to boycotting U.S. goods and swapping tips on local alternatives have popped up in several European countries.

In a Swedish Facebook group with more than 80,000 members, users ask for tips on buying non-American laptops, dog food and toothpaste. Members of a French group sing the praises of European laundry detergents and smartphone apps and debate whether cognac or Scotch whisky is the better alternative to bourbon.

There are also detailed discussion threads about what exactly constitutes an “American” product — does Coca-Cola manufactured in Europe count, or ice cream from Ben & Jerry’s, now owned by the British company Unilever? — that illustrate how boycotts in an era of globalized commerce are far from straightforward.

But the groups are mostly a place for anxious Europeans and others to share stories and vent about their opposition to U.S. policies.

Majken Jensen, 49, a coordinator for a government agency in Copenhagen, Denmark, acknowledged that many millions of people buy U.S. products worldwide, and boycotts by some consumers in a few countries may not make a huge difference at first. Still, she has stopped buying Oreos and Heinz ketchup and has swapped Estée Lauder night serum for a local brand, Beauté Pacifique.

“I’m not even a drop in the ocean,” she said. “But that’s my little way to protest.”

Jensen emphasized that her decision to stop buying U.S. goods was in opposition to the Trump administration, not the American people: “We want our friends back,” she said.

The backlash has led some stores to implement changes that make it easier for customers to identify local products.

Canada’s largest grocery chain, Loblaw, is using a “T” symbol to denote U.S.-made products that are more expensive because of retaliatory tariffs Canada recently put in place.