On Thursday, Jon Stewart ended his 16-year run as host of “The Daily Show” on Comedy Central, marking the end of an era that was significantly defined by Sept. 11, 2001.

Until that day, Stewart, the 39-year-old host, who had replaced Craig Kilborn in 1999, had been enjoying the early days of George W. Bush’s presidency, rife with humorous photo-ops and malapropisms (Remember “subliminable”?).

When Stewart returned to the air after the terrorist attacks, he addressed viewers with very little humor, a style he would revisit during moments of national tragedy like Charleston and Sandy Hook. Stewart spoke as a passionate and patriotic progressive, that unicorn that partisan media had all but erased from our memory. He spoke of his job as a “privilege” and pointed to the heroism of first responders as the “light” that is “democracy.”

And so began the unlikely crusade of the left-leaning Jewish comic from New Jersey defending the rights and dignity of those who bore the brunt of 9/11.

Stewart became a vocal supporter of the 9/11 First Responders Bill, designed to provide health care for ground zero workers suffering tragic health complications. After the bill was voted down by the Senate and blocked by a Republican-led filibuster, Stewart invited four New York first responders to appear on the show to detail their illnesses and the cost of treatments. The Senate passed the bill two weeks later, leading many, including the White House, to call Stewart instrumental to its passage.

Throughout the wars in Iraq and Afghanistan, Stewart questioned whether the wars were (a) going to reduce terrorism or (b) morally justified. In segments, subtitled “Mess O’Potamia,” Stewart questioned the existence of weapons of mass destruction in Iraq, warned of the consequences of preemptive war in an unstable region, and predicted growth of anti-American sentiment. While he wasn’t alone in voicing these concerns, Stewart’s approach resonated with his young, left-leaning, politically engaged audience. Stewart placed blame not at the feet of U.S. soldiers, but at the feet of U.S. leaders.

As soldiers began returning from war with traumatic brain injuries, post-traumatic stress disorder and high suicide rates, Stewart tackled the issue of veterans’ health. He highlighted our inability – or unwillingness – to care for our veterans with segments like “America’s Heroes Return: Operation Enduring Wait.”

For 16 years, Stewart has been a vocal, unforgiving critic of the right. But he has also been a critic of the left; for being weak (Senate Democrats), out of touch (Secretary of State John Kerry), muddled (Occupy Wall Street), or silent on important issues (Obama).

In spite of his partisan messaging, Stewart has rejected the vitriol we often see on cable news. When Stewart interviews conservative guests, his questioning is tough and pointed, but civil.

Like many of us, Stewart’s life changed on 9/11. His life didn’t change in some abstract way, but in a “the view from my apartment was the World Trade Center and now it’s gone” kind of way. Immediately after the attacks, Stewart admitted that “our show has changed. I don’t doubt that. What it’s become, I don’t know.”

Now we know.

“The Daily Show” became a defender of those whose lives were most affected by 9/11 and the wars that followed. It became a place where young people coming of age would turn for political perspective and respite from an often-dismal political reality. It became a critic of harmful media norms – incivility, sensationalism and ratings-driven news. It became a model of partisan talk that is simultaneously passionate, playful and polite.

It also became a place where we could be frustrated by politics but reaffirmed in our conviction that something better is possible.

As Stewart stated post-9/11: “I grieve, but I do not despair.”

This is what Stewart has given us during this trying period in our nation’s history. A place where we can weep for our ills, but laugh, knowing that something better is possible.

Grief without despair.