Writing for conservative Commentary magazine, Peter Wehner issues a stern warning about Glenn Beck [emphasis added]:

It's hard to tell how much of what Beck says is sincere and how much is for show. Whatever the case, and even taking into account the entire MSNBC lineup, Glenn Beck has become the most disturbing personality on cable television. One cannot watch him for any length of time without being struck by his affinity for conspiracies and for portraying himself as the great decoder of events.

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All this is quite troublesome in its own right. But what ought to worry conservatives in particular is that Beck not only has the unusual capacity to discredit virtually every cause he takes up; he also confirms the worst caricatures of the right.

Wehner also notes that it's “only a matter of time” before Beck “blows apart professionally.”