It seems that Rick Sanchez was a little too thin skinned and reacted to Jon Stewart's mocking him by stepping a little bit too strongly. Mr Sanchez stepped in the do-do, by making a broad criticism of Mr. Stewart. Mr. Sanchez based the criticism on the comedy star's ethnic group, as if some one other than Jon Stewart is responsible for Jon Stewart's humor.
In my humble opinion, the best way to battle comedians is with humor, with jokes, by mocking them, and not by making the wrong step of stepping into do-do, which is where responding in anger leads.
I think -- CNN reacted too quickly and wrongly, based on what Rick Sanchez said on that radio program. See the video. Maybe there are other issues between Rick Sanchez and CNN, and there is something missing in the story. Rick Sanchez was one of the best people CNN had. His firing is CNN's loss.
As for Jon Stewart? I think he is one of the best people on cable TV.