DURING THE 1930S, a beast called fascism stirred to life and began overwhelming societies across the world. Within 10 years, it was clear this had been one of history’s worst ideas. But the unappealing reality is that during the fascist moment, many, many people thrilled to its appeal — and not just in the places that would become the Axis powers in World War II.

Yet the United States didn’t go fascist. Why? In 1941, the journalist Dorothy Thompson wrote an unsettling article for Harper’s Magazine which asked the question, “Who Goes Nazi?” Based on her time spent in Europe — she was the first U.S. reporter expelled from Nazi Germany — Thompson explained, “Nazism has nothing to do with race and nationality. It appeals to a certain type of mind.” Moreover, Thompson wrote, huge swaths of Americans possessed this type of mind.

Looked at from a distance of nearly a century, the reason the U.S. evaded fascism seems clear. It wasn’t that we’re nicer or better than other countries, thanks to our inherent sterling character. We just got lucky. The prolate spheroid-shaped football of history bounced the right way for the country. And a huge part of that luck was Franklin D. Roosevelt and the New Deal.

Roosevelt was exactly the right president at the right time. The New Deal demonstrated that democracy could deliver unmistakable benefits, both material and emotional, to desperate people, and thereby drained away much of the psychological poison that powers fascism.

Then, over the next 30 years, something terrible happened: America forgot all this. We forgot how lucky we got. We forgot the New Deal was not a mountain range created by nature but an extraordinary achievement that was erected by humans and could therefore either be extended or destroyed.

Robert Kuttner illustrates this eloquently in his new book “Going Big: FDR’s Legacy, Biden’s New Deal, and the Struggle to Save Democracy.” Kuttner, born in 1943, writes, “I am a child of the New Deal. My parents bought their first home with a government-insured mortgage. When my father was stricken with cancer, the VA paid for excellent medical care. After he died, my mother was able to keep our house thanks to my dad’s veteran’s benefits and her widow’s pension from Social Security.”

The problem, he says, is, “My generation grew up thinking of the system wrought by the Roosevelt revolution as normal. … But this seemingly permanent social contract was exceptional. … Above all, it was fragile, built on circumstances and luck as much as enduring structural change.”