Apparently, no one knows where the saying came from, but by 1840 or so variations were appearing in etiquette guides: “Never talk about religion or politics,” especially at the dinner table.

This wisdom made the leap to popular culture in 1961, when the philosopher Linus commented in a Peanuts comic strip: ““There are three things I have learned never to discuss with people — religion, politics and the Great Pumpkin.” The Great Pumpkin is, of course, a faith issue for Linus.

Now, with that timeline in mind, please consider this follow-up question: Before 2016, does anyone remember reading waves of mainstream news stories near Thanksgiving built on horror stories about bitter political arguments around the extended-family holiday table? I mean, surely loved ones in the past argued about Richard Nixon, the nature of the Trinity, Bill Clinton’s private life, the quality of the modern hymn “On Eagles Wings” or other hot-button topics in religion and politics (or both)?

What happened in 2016 that suddenly made this a must-cover issue in elite newsrooms? Maybe this topic suddenly became urgent, for some reason, among journalists who had escaped heartland zip codes and found their true selves by moving to New York City and Washington, D.C.?

The New York Times published an archetypal feature of this kind the other day that ran with this dramatic double-decker headline:

Families Have Been Torn Apart by Politics. What Happens to Them Now?

Unlike 2016, when conflicts emerged over political choices, this time many are centered on the legitimacy of the result itself.

The overture follows the formula that readers have seen dozens of times in the past four years.

Tho Nguyen’s parents, who immigrated from Vietnam, were always Republican. They are Catholic and oppose abortion. Four years ago they voted for Donald Trump.

But nothing prepared Ms. Nguyen, 25, a medical student in Kansas, for how much politics would divide her family over the next four years, as her parents became increasingly passionate about the president.