In his first broadcast as host of the news satire program The Daily Show 16 years ago he appeared behind his desk and poked fun at the Monica Lewinsky scandal.

• Video: Stewart's five best moments on The Daily Show

On Thursday night, nearly 2600 episodes later, his last show went to air just after the first Republican primary debate – starring Donald Trump as a presidential candidate.

Sadly the show was taped before the debate.

Over those 16 years Stewart changed the way Americans viewed satire, politics and news.

As America blundered into the wrong war and then into a great recession deepened by corporate greed and political ineptitude, Stewart raged at the failings of the political and media institutions that had let a great nation down.

The Daily Show was launched in 1996 as a late evening topical satire program. Stewart, a little known comedian and TV host took over as host as well as a writer and producer in 1999 and immediately sharpened its focus.

He became obsessed with seeking out and skewering hypocrisy and was aided in this by a team of writers led by Ben Karlin, who had cut his teeth at the satirical paper The Onion.

Their modus operandi was to punctuate Stewart's monologue with clips of their targets speaking out of both sides of their mouths.

In one infamous segment they had George W Bush debating himself via a series of such clips.

The genius of the show was that it stayed funny while trading in such heavy material.

As The Daily Show matured, Fox News cemented itself as the voice of conservative America, sometimes promoting the Republican Party, sometimes bullying it. As a result Fox became a constant target of Stewart's.

Speaking of Stewart this week the Fox president Roger Ailes told the Hollywood Reporter, "He's a brilliant comedian. He's actually a very nice guy, and I saw him with his kids on the street. He's a good father. He has a bitter view of the world and you see it embodied in how he's reacting to Fox News, equating it with death'.

Though he never hid his liberal worldview Stewart has always been an equal opportunities offender.

He famously took on the CNN political program Crossfire, appearing as a guest only to demand the hosts "stop hurting America" with its mindless binary take on oppositional politics. Months later the show was cancelled and the CNN president Jonathan Klein admitting he agreed with Stewart.

In 2004 a Pew Research Centre poll found that 21 per cent of people aged 18 to 29 cited The Daily Show and Saturday Night Live as their regular sources for presidential campaign news, compared with 23 per cent who mentioned ABC, CBS or NBC's nightly news broadcasts. "A lot of them are probably high," Stewart observed at the time.

In 2007 a second Pew study found Stewart was the fourth most trusted news anchor in the US.

This accumulation of credibility and power has earned criticism for Stewart and The Daily Show.

While he piously attacks journalists for their failings, this line of argument goes, he shirks any responsibility to remain impartial in his own work.

Stewart has never accepted this criticism, insisting he is a comedian rather than a commentator.

When Fox News Sunday anchor Chris Wallace asked why Stewart criticised Fox's biases but was unashamed in his own, Stewart responded, "You're insane. Here is the difference between you and I – I'm a comedian first. My comedy is informed by an ideological background. There's no question about that".

Last year he told the Washington Post he was baffled that people kept on asking him about the standards his show should hold itself to, and whether or not there was a moral line he should not cross.

"What's so interesting to me is the concern that people have for the rules of the moral universe of comedy," he said. "But not as much concern for the moral universe of governance. I've never heard someone ask a leading figure, 'Where do you draw the line?' I hear that a lot to comedians: 'What's too far?' I don't think I've ever heard that with a president. What's too far? Solitary confinement? Incarceration for, you know, three-strikes-and-you're-out drug convictions? Bombing civilians?"

In an interview with Salon this week the academic and social critic Camille Paglia condemned Stewart for elevating "snark" in American political discourse.

"Jon Stewart is not a major figure," she said.

"I think Stewart's show demonstrated the decline and vacuity of contemporary comedy. I cannot stand that smug, snarky, superior tone. I hated the fact that young people were getting their news through that filter of sophomoric snark."

Stewart may well have been "snarky", but he was never cynical.

His targets were always the powerful who punched down rather than up, and his concern was always that American public life improve.

His basic humanity was often most clearly revealed when comedy failed him.

After the shooting of nine black congregants at prayer by a white racist in South Carolina earlier this year he began his opening monologue by telling viewers, "I have one job, and it is a pretty simple job. I come in in the morning and we look at the news and I write jokes about it … and then its just cha ching and I'm out door.

"But I didn't do my job today … I've got nothing for you."

Similarly when news broke last December that police would not be held responsible for the killing of the unarmed black man Eric Garner after a spate of similar police killings, Stewart began his show grimly.

"If comedy is tragedy plus time, I need more f---ing time," he said. "But I would really settle for less f---ing tragedy."

And one of his most revealing interviews this year was a sad and angry exchange with the former New York Times reporter Judith Miller, whose reporting – based on unnamed George W. Bush White House sources – in the lead up to the Iraq war helped convince skeptical Americans of the war's false premise.

"I believe that you helped the administration take us to, like, the most devastating mistake in foreign policy that we've made in, like, 100 years … but you seem lovely," he told her.

This was Stewart at his meanest, at his angriest. Normally his satire was tempered with courtesy, and that has been crucial to his success.

"He turned a feeble comedy show into the most honoured program on air, with 18 Emmy and 2 Peabody awards," wrote the former Bill Clinton advisor, Bill Curry of Stewart this week. "Most amazingly, he used a half hour on late night basic cable to challenge how we report politics and debate policy. By honest, reasoned, respectful debate he became America's most indispensable progressive."

That sense of Stewart's decency was obvious in the farewells he has received in recent weeks.

Ending an interview late last month, President Barack Obama grasped his hand and said, "You've been a great gift to the country." The two have quite a history. When he first appeared on the show as an ascendant senator Obama told Stewart, "The only person more overhyped than me is you." Stewart responded, "That's about the best answer I think I've ever heard."

His farewell show included tributes from a cross section of public figures, including many of Stewart's targets. There was Rahm Emmanuel, Obama's former chief of staff and the current mayor of Chicago, Senator John McCain, Hillary Clinton ("Just when I'm running for president. What a bummer," she said) and even the Fox star Bill O'Reilly.

More tellingly there were the comedians who Stewart fostered – Stephen Colbert, Jon Oliver and Larry Wilmore among them.

Colbert is about to take over as David Letterman's late night replacement. Oliver and Wilmore are already hosting shows in a similar vein to The Daily Show.

"Bullshit is everywhere," Stewart said by way of conclusion. "There is very little you will encounter in life that has not been somehow infused with bullshit … So if you smell something."