Predictably, Levin’s response post is saturated with derision, just like his radio show, whose motto seems to be “That’s right! I said it!”

Levin is no stranger to calling out political opponents in harsh terms. This is true.

....I'm not seeing this "saturation of derision" you refer to in his response.

If by "derision," you mean that he strongly refutes Manzi's points, I suppose you could make such a claim.

...It was not Mark Levin who dismissed someone who disagreed with him as a wingnut.