Rarely has a political drama so depressed me as the Dianne Feinstein swan song. Like her or loathe her, Feinstein has been a towering political figure throughout the past nearly half-century of California history. She was the one on the scene when San Francisco supervisor Harvey Milk and Mayor George Moscone were assassinated in November 1978, and she became the mayor of San Francisco in the wake of this double murder.

In 1992, Feinstein was elected as a US senator, filling a vacant seat left by Republican Pete Wilson, who had been elected governor of California in 1990. Her election, in tandem with that of several other high-profile women, led to 1992 being dubbed the “Year of the Woman” by the media.

In the 30 years that Feinstein has been a senator, she’s had her fair share of controversies and fights­—pissing off everyone from the California Democratic Party, with her staunch support for the death penalty, to President Obama, with her determination that the full Senate report on black-site torture of terrorism suspects be declassified and released to the public. She has also been a hugely important legislator, committee chair, and advocate for California.

Feinstein has, by any measure, played an outsize, larger-than-life role in state and national politics for an awfully long time. How terribly sad, and how demeaning, then, is her final act on the D.C. stage.

The nearly 90-year-old senator returned to Washington a few weeks ago, after a months-long absence. She promptly told the media that she hadn’t been away and had been working in D.C. the whole time. She denied­ that she had suffered encephalitis—and then had to be informed by her own staff that she had indeed experienced this side effect from shingles. These are not the utterances of someone who is entirely on the ball.

Most depressing of all, however, have been the recent media reports that the senator is being wheeled into the Senate each day to cast her votes on key bills and nominations­. She has to stay near the door, though, so that her support crew can whisper cues in case she forgets her lines, telling her how to vote and explaining, in simple terms, the debates of the day. This, not to mince words, is zombie politics.

Of course, the more Feinstein is visibly unable to perform even the most basic of senatorial duties, the more old stories are dusted off and repeated anew. That is, after all, what media feeding frenzies are. Witness the recent flurry of stories that, last year, Feinstein was so confused about institutional procedures in the Senate that she didn’t understand why Vice President Kamala Harris was in the building to cast a tie-breaking vote. Or the reports, dating back to last year, and now endlessly looped, that the senator frequently can’t remember the names of her close colleagues.

When my university writing students hand in otherwise good drafts with mediocre endings, I make sure to tell them that the ending is what everyone remembers. It’s like a meal at a restaurant: No matter how good the appetizer and entrée are, if the dessert is moldy or crawling with bugs, it’s a fair bet that that’s the memory diners will take away with them.

Feinstein has led an extraordinary life and career, but the longer she clings to her Senate seat despite a manifest incapacity to live up to the rigors of the job, the more likely it is that this is how she will be written into the history books. What we are witnessing now is the moldy dessert. She will be seen not as larger than life but as desperately diminished, fragile, and, yes, entirely incompetent. Hers will be read as a cautionary tale of hubris, as an example of desperate inelegance from a star performer too addled to take her final bows.

Two-thirds of Californians tell pollsters they think that Feinstein is unfit to stay as their senator. A majority of Democratic voters want her to resign. (I suspect, in their defense, that those who answer that they don’t want her to resign simply haven’t been reading the news about her state of acute unwellness.) Yet resign she won’t, and none of those who might influence her­—from California Governor Gavin Newsom to ex-speaker of the House Nancy Pelosi to Senate majority leader Chuck Schumer­—are willing to publicly push for her to go.

Because of the utterly unrepresentative nature of the US Senate, Californians are already scandalously underrepresented in D.C. It takes nearly 40 times as many residents from the Golden State to elect their US senators as it does Montanans to elect theirs. And now, because of Feinstein’s unfathomable stubbornness, for all intents and purposes California is down to only one fully functioning senator.

I agree with GOP presidential hopeful Nikki Haley on almost nothing of political substance. But she’s not wrong when she says that aged political leaders ought to face regular mental competency tests, in the same way as elderly drivers have to regularly retake parts of the driving test to weed out those who have become too impaired to safely navigate the roadways. If there were such a competency test for politicians, Californians would almost certainly be getting ready, right about now, to welcome a replacement for their senior senator.

We in the punditocracy regularly bemoan the scale of political disengagement and cynicism toward the political process displayed by the American public. We lament how few young people vote­—27 percent of 18-29-year-olds in last year’s midterms, and that was one of the highest turnouts in the last 30 years—and how few of them understand the way the political system and its institutions function. But how can we expect young people to be engaged when they look at Feinstein, a woman old enough to be their great-grandmother, see her befuddlement, and then are asked to accept the fact that, since she refuses to resign and there are no mechanisms in place to rule her incompetent, she will continue to represent 40 million Americans for nearly two more years?