He was invited on Crossfire to promote a book.
The Book - Step 1 in becoming self important.
The Appearances - Step 2
The Being Unruly and Getting His Appearance Mentioned On Other Shows - Step 3
They all follow that procedure.
1. The Book was written by the staff (and others I assume) from the Daily Show - it was not "His" Book.
2. Has not nearly as much to do with Self Importance as it does marketing.
3. Did you watch the show? His behavior can hardly be considered unruly especially compared with many other guests I've seen on Crossfire in the past.
As for having it on other shows? I've heard and seen it on the net far more than I saw any sustained covereage of it on television. Various Media oriented sites, as well as numerous personal and political blogs.
If Stewart feels self important, it might be more likely due to the nice fat contract he got the last time The Daily Show was renewed, as opposed to the Crossfire appearance. Crossfires' ratings were such, that no guest should have ever felt self important for being invited.
And what office is He currently running for? Until he actually throws his hat in the ring for something, the Politician label just doesnt hold true.
If you don't like his comedy, that's fine by me, but I don't see where he is doing anything differently now than when he first sat down at that desk. Political Humor is most often driven by the Parties and Persons in power. I'm sure that The Daily Show would love to throw some Clinton jokes in there, but they would feel a little stale right about now, don't you think?