Political life in America never ceases to astonish. Take last week’s pronouncements from the Republican Presidential field. Please. Mike Huckabee predicted that President Obama’s seven-nation agreement limiting Iran’s nuclear capabilities “will take the Israelis and march them to the door of the oven.” Ted Cruz anointed the American President “the world’s leading financier of radical Islamic terrorism.” Marco Rubio tweeted, “Look at all this outrage over a dead lion, but where is all the outrage over the planned parenthood dead babies.” And the (face it) current front-runner, the halfway hirsute hotelier Donald Trump, having insulted the bulk of his (count ’em) sixteen major rivals plus (countless) millions of citizens of the (according to him) not-so-hot nation he proposes to lead, announced via social media that in this week’s Fox News debate he plans “to be very nice & highly respectful of the other candidates.” Really, now. Who’s writing this stuff? Jon Stewart?

Over the decades, our country has been lucky in many things, not least in the subversive comic spirits who, in varying ways, employ a joy buzzer, a whoopee cushion, and a fun-house mirror to knock the self-regard out of an endless parade of fatuous pols. Thomas Nast drew caricatures so devastating that they roiled the ample guts of our town’s Boss, William Marcy Tweed. Will Rogers’s homespun barbs humbled the devious of the early twentieth century. Mort Sahl, the Eisenhower-era comic whose prop was a rolled-up newspaper, used conventional one-liners to wage radical battle: “I’ve arranged with my executor to be buried in Chicago, because when I die I want to still remain politically active.” Later, Dick Gregory, Richard Pryor, and Joan Rivers continued to draw comic sustenance from what Philip Roth called “the indigenous American berserk.”

Four nights a week for sixteen years, Jon Stewart, the host and impresario of Comedy Central’s “The Daily Show,” has taken to the air to expose our civic bizarreries. He has been heroic and persistent. Blasted into orbit by a trumped-up (if you will) impeachment and a stolen Presidential election, and then rocketing through the war in Iraq and right up to the current electoral circus, with its commodious clown car teeming with would-be Commanders-in-Chief, Stewart has lasered away the layers of hypocrisy in politics and in the media. On any given night, a quick montage of absurdist video clips culled from cable or network news followed by Stewart’s vaudeville reactions can be ten times as deflating to the self-regard of the powerful as any solemn editorial—and twice as illuminating as the purportedly non-fake news that provides his fuel.

Stewart grew up in New Jersey. He was schooled at William & Mary, in Virginia. Adrift for a while, he took odd jobs. He tested mosquitoes from the Pine Barrens for encephalitis. He put on puppet shows for disabled children. At the Bitter End and other clubs around the city, he studied all the varieties of standup. He proved especially fluent in a meta-Borscht Belt post-Friars Club rhythm_._ As a performer, Stewart is nearly as connected to Molly Picon and Professor Irwin Corey as he is to George Carlin.

On January 11, 1999, he made his début as “The Daily Show’s” host, replacing a less political wisenheimer named Craig Kilborn. Initially, Stewart seemed ill at ease with the trappings of his position. He wore a suit that first night, and, in the midst of an interview with the actor Michael J. Fox, he blurted, “Honestly, I feel like this is my bar mitzvah. I’ve never worn something like this, and I have a rash like you wouldn’t believe.” The evening was rounded out by a report on the Clinton impeachment hearings by Stewart’s “chief political correspondent,” a young improv comic named Stephen Colbert.

Stewart soon found his footing, and what he became, with the help of his writers, his co-stars, and a tirelessly acute research team, was the best seriocomic reader of the press since A. J. Liebling laid waste to media barons like William Randolph Hearst and Colonel Robert R. McCormick. Stewart demonstrated that many of the tropes favored by the yellow press of Liebling’s day have only grown stronger. “There is no concept more generally cherished by publishers than that of the Undeserving Poor,” Liebling wrote. The contempt that he found in the plutocrat-owned, proletarian-read press, Stewart found on Fox News—particularly in ersatz journalists like Stuart Varney, a sneery character out of Dickens who regularly goes on about “these so-called poor people” who “have things” but “what they lack is the richness of spirit.” Stewart’s evisceration of Varney was typically swift and unforgiving. Perhaps his greatest single performance came in 2010, with a fifteen-minute-long bravura parody of the huckster and conspiracy theorist Glenn Beck.

There was always something a little disingenuous about Stewart’s insistence that he is a centrist, free of ideological commitment to anything except truth and sanity. In fact, his politics tend to lean left of center. He’s been aggressive toward, and ruthlessly funny about, unsurprising targets from Donald Rumsfeld to Wall Street. His support for L.G.B.T. rights, civil rights, voting rights, and women’s rights has always been unambiguous. His critique of Obama is generally that of the somewhat disappointed liberal, particularly on issues like Guantánamo and drones. But Stewart is a centrist only in this sense: he is not so much pro-left as he is anti-bullshit.

At the same time, he has occasionally dropped the nightly gagfest to reveal flashes of earnest anger and unironic heart. Just after 9/11, he began his program with a personal monologue: “The view from my apartment was the World Trade Center. And now it’s gone. And they attacked it, this symbol of American ingenuity and strength, and labor and imagination and commerce, and it is gone. But you know what the view is now? The Statue of Liberty. The view from the south of Manhattan is now the Statue of Liberty. You can’t beat that.” More recently, after a grand jury on Staten Island failed to bring any charges related to the death of Eric Garner, an African-American whose crime was the sale of loose cigarettes, Stewart declared himself dumbstruck. “I honestly don’t know what to say,” he told his audience. “If comedy is tragedy plus time, I need more [bleep]ing time. But I would really settle for less [bleep]ing tragedy.” Similarly, after this year’s mass murder in Charleston, Stewart said, “I honestly have nothing other than just sadness, once again, that we have to peer into the abyss of the depraved violence that we do to each other and the nexus of a just gaping racial wound that will not heal yet we pretend doesn’t exist.”

Stewart set out to be a working comedian, and he ended up an invaluable patriot. But the berserk never stops. His successor, Trevor Noah, will not lack for material. As Stewart put it wryly on one of his last nights on the air, “As I wind down my time here, I leave this show knowing that most of the world’s problems have been solved by us, ‘The Daily Show.’ But sadly there are still some dark corners that our broom of justice has not reached yet.” ♦