Mark Levin asks, in effect, why people are piling on poor Trent Lott who didn't give Bill Clinton a hard time for honoring William Fulbright.
Answer: People aren't piling on Lott for honoring Thurmond. We're not complaining about the fact that he appeared at the cryogenic old lecher's birthday party, or that he gave a speech lauding his accomplishments. We're complaining about the fact that he expressed regret that Thurmond didn't win the presidency in 1948 on a platform of explicit racism, and that he suggested that the fifty years that followed would have been better if Thurmond had won and been able to block anti-lynching legislation, civil rights legislation, and so on.
The analogous behavior for Clinton would have been endorsing the Southern Manifesto. This, he did not do.