9/11 Anniversary: A Look Back At The Return Of Letterman, Jon Stewart & More (VIDEOS)

We've all heard the phrase, "Tragedy + Time = Comedy," but what if you're a comedian in the midst of a tragedy who must return to work even though not nearly enough time has passed? If you can't be funny, all that's left is to be honest.

In the weeks that followed the September 11 terrorist attacks, late night hosts, comedy writers, and satirists of all stripes slowly returned to the job, in part because it felt like their duty. For those comics who lived and worked in New York City -- like Letterman, Jon Stewart & Conan -- it was a moral imperative. Their city needed them to try to make things normal again.

Those first shows, episodes and issues covered a lot of ground and their tone reflected how close to the event they were. In the case of Letterman, recovery efforts and Ground Zero were in full swing and the true number of those lost was still in question. In the case of South Park, a couple of months had passed and the United States had already begun the war in Afghanistan.

Over the days, weeks and months, laughter was slowly allowed to replace tears, even though the loss and frustration remained. In their own way, these comedians ushered us through each stage of grief. Which ones do you remember and whose message resonated most with you?