Almost exactly a year ago, ABC announced it would reboot one of its most beloved sitcoms, putting its star back in the national spotlight. "There's really no one better to comment on our modern America than Roseanne," ABC Entertainment president Channing Dungey said at the time.

The implication was clear: Roseanne Barr, and the working-class mom she played on TV, would be a perfect fit for the Trump era. Hollywood executives were scrambling to create shows that depicted the struggling blue-collar Midwesterners who, in the popular imagination, helped propel Donald Trump to the White House.

"Roseanne," it seemed, would help lead the charge.

But even then Barr, 65, was far from an anodyne personality — as ABC surely knew. She already had a reputation as a political provocateur, staking out iconoclastic positions on both the left and right. And she had stoked controversy over her decades in the limelight, most recently on her Twitter feed.

The apparent contradiction — mainstream TV hit-maker and outrageous online agitator — could not, in the end, be resolved, as ABC demonstrated Tuesday afternoon by canceling the "Roseanne" revival. The network cited the comedian's "abhorrent, repugnant" tweet about Valerie Jarrett, a former senior adviser to Barack Obama.

If President Trump, who called Barr to congratulate her on the premiere of the reboot in March, or another right-wing figure condemns ABC's decision, the cancellation could open up a new front in the culture wars, particularly disputes over the limits of free speech and artistic censorship.

ABC's move capped off months of fierce debate over the show. The reboot was an instant (and perhaps unexpected) hit, but it invited controversy at seemingly every turn. Roseanne Conner, the lovable loudmouth played by Barr, was an outspoken supporter of Trump, and some episodes pitted her against liberal-minded relatives.

A joke about network shows that star racial minorities — a nod to fellow ABC sitcoms "black-ish" and "Fresh Off the Boat" — stirred up outrage, with many viewers and commentators finding it dismissive of cultural diversity. Another episode was criticized as Islamophobic.

All the while, Barr maintained an active presence on Twitter, where she raised eyebrows by spreading disinformation and some politically incendiary messages.

She tweeted, for example, about a conspiracy theory involving Trump purportedly busting a child sex trafficking ring. She accused David Hogg, a survivor of the Parkland school shooting and a proponent of gun control, of giving a Nazi salute.

Roseanne's reputation as a provocateur was arguably nothing new, even before the recent scrutiny on her public statements.

She was harshly criticized by President George H.W. Bush for a "disgraceful" rendition of the national anthem at a baseball game in July 1990. The performance was widely seen as flagrantly off-key. She followed it by grabbing her crotch and spitting on the ground, perhaps mimicking the rituals of baseball players.

And in 2009, Barr was pilloried for posing as Adolf Hitler for a satirical Jewish-themed publication called Heeb. Three years later, in early 2012, Barr launched a candidacy for the Green Party presidential nomination, ultimately losing to Jill Stein.

But the swirl of controversy did not, at least for a couple months, prompt ABC to take any action. Barr's social media activity was reportedly the subject of a joke at ABC's annual upfront presentation this month — but the network seemed to be turning a blind eye.

That all changed after Barr, in a tweet, referred to Jarrett, the former Obama adviser, as a "child" of the "Muslim Brotherhood" and "Planet of the Apes." Dungey, the ABC president, blasted that comment in a news release, saying it was "inconsistent with our values."

Barr apologized for her tweet, saying on Tuesday morning she was sorry "for making a bad joke" about Jarrett's politics and her looks. About three hours later, Dungey released a statement saying ABC would cancel "Roseanne."

Barr later apologized again to fans, saying she had been "Ambien tweeting" — a reference to the prescription sleeping aid — and to "the hundreds of people, and wonderful writers (all liberal) and talented actors who lost their jobs on my show due to my stupid tweet."