Donald Trump last night offered a funhouse mirror version of one of the greatest speeches in American history: Franklin Delano Roosevelt’s first inaugural address, in 1933. In the midst of a genuine crisis, the Great Depression, FDR began by emphasizing his “firm belief that the only thing we have to fear is fear itself -- nameless, unreasoning, unjustified terror.”

Trump sought to foster exactly that. For Trump, “America is a more dangerous environment for everyone than frankly I have ever seen and anybody in this room has ever watched or seen.“

Quietly and wryly, Roosevelt observed, “We are stricken by no plague of locusts.” He added: “Compared with the perils which our forefathers conquered because they believed and were not afraid, we have still much to be thankful for.”

In Trump’s account, by contrast, the United States is in the midst of “death, destruction, terrorism and weakness,” pervaded by “poverty and violence at home.” He depicts a nation facing an unambiguously existential threat: “The attacks on our police, and the terrorism in our cities, threaten our very way of life.”

Behavioral scientists distinguish between fast thinking and slow thinking. Fast thinking is represented in the mind’s System 1; it is automatic, intuitive, and often emotional. Slow thinking, reflected in System 2, is deliberative and reflective; it likes statistics. It’s hard to think of a purer System 1 candidate than Trump. (Hillary Clinton, by contrast, is all System 2.)

But System 1 candidates come in radically different forms, and with his effort to trigger unreasoning fear, a sense of situations spiraling out of control, and his constant projection of rage and outrage, Trump is something unprecedented.

John F. Kennedy and Ronald Reagan were System 1 candidates too, in the sense that they were able to appeal directly to people’s intuitions and emotions. But like Roosevelt, they induced a smile and a laugh, and they exuded a sense of comfort and calm, not hysteria.

Criticized for choosing his brother Robert, just 35 years old, to be Attorney General, Kennedy responded, “I don’t see anything wrong with giving Bobby a little legal experience before he goes out on his own to practice law.” Asked in his debate with Walter Mondale whether he was too old to be re-elected president, Reagan, then 73, quipped, ”I will not make age an issue of this campaign. I am not going to exploit, for political purposes, my opponent‘s youth and inexperience.“

Both Kennedy and Reagan were alert to genuine dangers, domestic and international, and they were hardly reluctant to call attention to them. Reagan’s depictions of the Soviet Union occasionally alarmed Democrats. But he was raised on Roosevelt, and he liked to quote him, and he exuded optimism and good cheer. In his entire life, he never gave a speech like Trump’s last night.

If we are looking for a predecessor, it’s Richard Nixon. But the comparison misses important differences. Nixon practiced the dark arts, but he was mostly a System 2 candidate. Trained as a lawyer and with a sharp eye for detail, he lacked visceral appeal. He was also a complicated figure. For all his talk of order, he could be gentle and open, and he was able to capture in his 1968 acceptance speech the characteristic buoyancy of his fellow citizens: “Just to be alive in America, just to be alive at this time is an experience unparalleled in history.”

The U.S. is an optimistic nation. No candidate has ever won the American presidency by speaking primarily to people’s deepest fears and by manufacturing a sense of apocalypse -- that our leaders “can’t do anything right,” that things are utterly falling apart.

As the actual vote comes closer, System 2 usually kicks in; unless System 1 candidates make substantive arguments, they start to look like the one you might date but won’t marry. Kennedy and Reagan were able to meet that challenge. It will be a real struggle for Trump.

But the electorate is uneasy about both of the major candidates, and sometimes the past isn’t prologue. This time might be different.

By Cass R. Sunstein

Cass R. Sunstein is a Bloomberg View columnist. He is the author of “The World According to Star Wars” and a coauthor of “Nudge: Improving Decisions About Health, Wealth and Happiness.” -- Ed.

Bloomberg