how does this lunatic bigot stay on the air?

Glenn Beck to Muslim-American guest: “How do we know the difference between you and those that are trying to kill us?” In Nov. 2006, Beck made a similar comment to Rep. Keith Ellison (D-MN). “I have been nervous about this interview with you,” Beck said, “because what I feel like saying is, ‘Sir, prove to me that you are not working with our enemies.’”

(Think Progress)
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I am absolutely serious - how can someone make these kinds of offensive, bigoted remarks and remain on the air? Aren't there rules against hate-speech on the airwaves?