People gather and hold candles to support women's rights Friday in Brussels. The protest is in solidarity with the Women's March in Washington. (Stephanie Lecocq/European Pressphoto Agency)

BRUSSELS — This is an organization town, and Donald Trump has dedicated himself to smashing the system. So his inauguration Friday was greeted with sadness, concern and even despair in the home of the European Union and NATO.

In the Beaux-Arts center of the city, more than 1,000 people turned out the Place de la Monnaie to protest his presidency, try to protect the transatlantic alliance he has vowed to upend and join in solidarity with the Women's March scheduled for Saturday in Washington.

In a city where many people work for vast organizations that devote themselves to tearing away borders and bolstering international alliances, Trump’s arrival in Washington threatens the ideals many have devoted their careers to upholding. And it gives sustenance to the anti-immigrant, anti-establishment forces who are challenging mainstream leaders in elections this year in France, Germany and the Netherlands.

“The atmosphere is one of great uncertainty,” said Antonio Fernandez, a Spanish citizen who manages research grants at an office of the European Commission and took part in the protest. “He seems to be determined to undermine the European Union and everything it represents.”

In part because of Trump, in part because of the British vote to leave the European Union — which helped fuel Trump’s insurgent campaign — “I don’t know if the European Union is going to be here in 10 years,” Fernandez said.

Other Brussels protesters were simply concerned about his policies toward women, Muslims and world affairs. More than a thousand people chanted, banged on drums and vowed to oppose Trump for the next four years. When Trump was sworn in — at 6 p.m. Brussels time — a howl lifted up from the crowd.

“It’s a topic in every work lunch,” said Monique Gerwers, who works in internal communications at a polyurethane manufacturer about 15 miles north of Brussels. “It’s so sad to have someone like Trump in control.”

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