The visitor looked to his left as he stepped onto Fifth Avenue but forgot that in America traffic flows the opposite direction than in his native England. He never saw the car coming.

“I do not understand why,” Winston Churchill later said of being hit by a car that night in New York City in December 1931, “I was not broken like an eggshell or squashed like a gooseberry.”

After a visit to nearby Lenox Hill Hospital to clean up a nasty scalp wound and two cracked ribs, Churchill ended up being fine. What would the next 20 years of 20th century history have looked like if that car had been going just a little bit faster?

As we wait for the results of the 2020 election — with at least a little and, potentially, quite a lot of time to kill — it is worth pondering the randomness of history. A slight turn here or there, a little more of this or a little less of that, and we live in a very different world.

There is no more vivid recent example of the phenomenon than the two tragic figures of Democratic politics over the past generation: Al Gore and Hillary Rodham Clinton.

Both had limitations as politicians, and by their own reckonings made errors in their campaigns. But let’s never forget that both also won the popular vote. Were it not for arguably illegitimate and inarguably freakish circumstances they would have both won the presidency, too. Instead the White House ambitions that they had spent their professional lives advancing were broken like an eggshell and squashed like a gooseberry.

It has been a star-crossed start to the 21st century, which will be one-quarter over by the time whoever is elected today finishes his term. When it comes to Gore and Clinton, no one can say where paths not taken would have led. But both figures invite tantalizing, even agonizing, flights of counter-factual speculation. The lull before this evening’s storm is a fitting moment to ponder might-have-beens.