How does Trump’s divided America look to foreign eyes? A Pew study in the spring found that global confidence in the U.S. president had fallen from 64 percent at the end of Obama’s tenure to 22 percent at the start of Trump’s. Those expressing “no confidence” surged from 23 percent to 74 percent.

Foreign nations have bet on our country’s internal divisions before, but they’ve mostly been wrong. Abraham Lincoln’s persistence preserved the Union, even as some European nations thought the United States would splinter. Franklin Roosevelt’s fireside chats helped keep America together during the 1930s when some left-wing and right-wing agitators were urging violence, and fascism and communism abroad seemed the wave of the future.

This country’s vulnerability to manipulation was vividly described in a 1945 report by Britain’s Secret Intelligence Service, which reviewed that nation’s covert-action campaign starting in 1940 to push the United States into war.