Equal opportunity defamer?

According to Frank Rich's column in today's New York Times, Jerome Corsi, author of the cleverly titled The Obama Nation (and earlier co-author of the Kerry smear book Unfit to Command), has accused the McCain campaign of accepting substantial contributions from a group with links to Al Qaeda (see here) and claimed that "McCain's personal fortune traces back to organized crime in Arizona" (see here). For what it's worth, Corsi has also insinuated a link between the McCain campaign and Russian organized crime.

Rich observes:

Corsi's writings have been repeatedly promoted by Sean Hannity on Fox News; Corsi's publisher, Mary Matalin, has praised her author's "scholarship."

Nevertheless, there are some people on the right side of the political spectrum, like Jon Henke, who characterize Corsi as a "smear artist" who has made "gross errors" and is one of the "hatchet men, bullies and political hit men" who "serve to discredit us [conservatives] all."

Then, again, if Hannity and Matalin are right about Corsi, should we, as Rich suggests, take him seriously about McCain?