Why don't I let a scholar of history answer for me. Directly from the above article:
"Ron Radosh, one of the most reputable scholars who has studied the McCarthy era in great detail, is appalled at the damage Coulter has done to the work he and many others have painstakingly done over the years.
“I am furious and upset about her book,” he told me last week. “I am reading it — she uses my stuff, Harvey Klehr and John Haynes, Allen Weinstein etc, to distort what we actually say and to make ludicrous and historically incorrect arguments.
This is a curious statement. Radosh is refered to exactly three times in Ann's book and she provides footnoted quotes of the sources that she uses in two cases and simply refers to the book that he wrote about the Rosenbergs in the third.