If 2025 goes down as the year the trans-Atlantic alliance broke down, future historians will marvel at just how far national leaders strayed from the “grassroots” in Europe and America.

Despite the heavy cost of defending Ukraine’s sovereignty — and even as most Europeans have lost faith in the United States as a reliable ally — voters on both sides of the Atlantic remain surprisingly united in their support for the beleaguered country. As talks proceed between the U.S., France, the United Kingdom, Poland and Germany, popular support for Ukraine will be a key finding to bear in mind.

In surveys we conducted across the U.S. and four major European countries this month, we found that clear majorities in all countries still back the key tenets of the NATO alliance. Only among far-right Alternative für Deutschland (AfD) voters and U.S. Republicans do significant pockets of disagreement emerge; and even in these cases, voters are divided.