Some estimates project that at least one million refugees will flee Ukraine because of the Russian invasion. Linda Thomas-Greenfield, the U.S. ambassador to the United Nations, said this past week that the fighting could uproot as many as five million people, “putting pressure on Ukraine’s neighbors.”

Diplomats and experts said European states that are willing to take in Ukrainians might be trying, in part, to highlight Russian aggressions against civilians by offering a humanitarian response. “If you think of causing the refugee crisis as one of Putin’s tools to destabilize the West, then a calm, efficient, orderly response is a really good rebuke to that,” said Serena Parekh, a professor at Northeastern University in Boston and the director of its politics, philosophy and economics program.

“On the other hand,” said Ms. Parekh, who has written extensively about refugees, “it’s hard not to see that Ukrainians are white, mostly Christian and Europeans. And so in a sense, the xenophobia that’s really arisen in the last 10 years, particularly after 2015, is not at play in this crisis in the way that it has been for refugees coming from the Middle East and from Africa.”