A polite streak broken by Clinton and Trump: Looking back at 40 years of handshakes.

Wednesday night’s final face-off between Hillary Clinton and Donald Trump appears to be historic in at least one measure: the first time presidential candidates didn’t shake hands while sharing a debate stage.

We reviewed YouTube’s archives of presidential debates, and we found an unbroken streak of handshakes dating all the way back to the first time Gerald Ford faced Jimmy Carter in 1976. There were three debates that year, and footage of the second and third show handshakes between the rivals. It’s probably a safe bet they shook hands in the first debate, too, but the video footage was incomplete.

The handshake streak almost died during the second presidential debate of 2016, when Clinton and Trump kept to their sides of the stage at the start of the Oct. 9 event in St. Louis amid the fallout over Trump bringing women who accused Bill Clinton of sexual assault. But the two candidates ended up keeping the tradition alive by shaking hands at the end.

That wasn’t the case Wednesday night: Clinton and Trump avoided contact at the start and the end. That’s probably an unprecedented moment — or, more accurately, an unprecedented lack of a moment.

Here’s a look back at America’s lost tradition of courteous greetings among its presidential candidates.

This story was originally published October 20, 2016 at 4:01 PM with the headline "A polite streak broken by Clinton and Trump: Looking back at 40 years of handshakes.."