Far as de Borchgrave goes, I have heard the man on C-Span, and FWIW he seems like an old-time Who, When, Where, What, Why kind of reporter. Didn't seem to have any blatant agenda.
Indeed, he exposed the methods used by left wing editors to supress much of the Communist atrocities in Vietnam, plus the subseriant relations of the VC to the North Vietnamese regime. One method used was the fictionalised account in his novel "The Spike".
I think if read closely you'll see that he doesn't approve of or agree with the notion of terrorism as a legimate tool, but is merely reporting the way some see it.
As an aside, guerilla warfare and terrorism are not the same thing. A matter of targets and to a lessor extent means. Guerilla warfare is a legitmate means for a weaker group to fight a stonger occuppying force. Thats why its a specialty of Special Forces, who in turn are to teach it to indigenous forces.