This was the problem all along: Having “Roseanne” back meant having Roseanne back.

In her relative absence from popular culture — say, in the time between when ABC’s “Roseanne” first ended in 1997 and when the network revived the sitcom this March to impressive ratings — Roseanne Barr acquired or developed some opinions that a few people, sadly, may agree with, but that everyone should find appalling.

Barr’s tirades, which often drew from right-wing conspiracy theories, were no big secret; Twitter is an irresistible flame to a certain kind of celebrity moth, and Barr had trolled around many times before, under cover of free speech and her provocative brand. But it all caught up to her on Tuesday after she posted several tweets, one of which, about former White House adviser Valerie Jarrett, was particularly racist. By midafternoon, ABC had canceled “Roseanne” — as well it should have.

What Barr did Tuesday is, unfortunately, not a bizarre occurrence in America right now. Many of us have experienced a return home or a reunion with old friends only to find that the conversational dynamic has shifted toward an ugly and unacceptable place. Blame Fox News, blame Infowars, blame the rise of Donald Trump — whatever mechanism of good manners used to direct traffic between people’s darkest thoughts and their big mouths has atrophied. Your grandfather changed. Your aunt changed. Your next-door neighbor planted Trump signs all over her yard. A high school classmate posted a racist cartoon on Facebook.

This is what the producers of “Roseanne” wanted to get at, sort of, from a sideways approach. Though it’s easy to disparage both them and ABC now for their combined failure to see this disaster building, I still take them at their word when they say they wanted to bring Barr back as the same middle-American Roseanne Conner whom we once loved, at her full volume, only to discover that she, too, voted for Trump. Why? How?

In setting up comedy premises about American families, the people who make television can’t go on forever pretending that half the country doesn’t exist as potential lead characters for fictional shows. Viewers were meant to be intrigued by that conservative pull on someone they loved — and by the idea that members of the Conner family (particularly Roseanne’s sister, Jackie, played by Laurie Metcalf) found Roseanne’s politics to be, at best, in error, and at worst, misguided.

Yet the show failed to fully build on that premise, choosing instead to dip a topical toe in here and there, letting us see a Roseanne full of contradictions, rather than confront the beast head-on: Roseanne and her husband, Dan (John Goodman), struggle to keep up their prescriptions because they’ve fallen through some crack in our health-care system; Roseanne is battling an addiction to opioids; Roseanne learns a small measure of tolerance from her new Muslim neighbors.

The ratings were high (tellingly high), yet the outcry was steady from those who would never distinguish the character from the actress who played her. And why should they? If we’ve learned anything from this, it’s that Roseanne is Roseanne is Roseanne. TV still needs a contrary, can­tankerous character from which to tell the story of American life and politics in 2018. But Barr was never the right person for that job.