Curt Cardwell has raised the question of the origin of the claim, supposedly by General Giap, that the anti-war protesters contributed to the success of the North Vietnamese in the war.

Ed Moise has already tackled this one [in a review of] Vo Nguyen Giap and Van Tien Dung, How We Won the War. Philadelphia: Recon Publications, 1976. 63 pp.

This book has been the subject of several unfounded rumors on the Internet. The first one began in the late 1990s. Supposedly, General Giap had written in How We Won the War that in the aftermath of the Tet Offensive of 1968, the Communist leaders in Vietnam had been ready to abandon the war, but that a broadcast by Walter Cronkite, declaring the Tet Offensive a Communist victory, persuaded them to change their minds and fight on. This rumor was entirely false. Giap had not mentioned Cronkite, and had not said the Communists had ever considered giving up on the war.

Several variants of this rumor appeared in 2004. In these, Giap is supposed to have credited either the American anti-war movement in general, or John Kerry's organization (Vietnam Veterans Against the War) in particular, for persuading the Communist leaders to change their minds and not give up on the war. Giap is sometimes said to have made this statement in How We Won the War, sometimes in an unnamed 1985 memoir. All versions of the rumor are false. Neither in How We Won the War, nor in any other book (the 1985 memoir is entirely imaginary), has Giap mentioned Kerry or Vietnam Veterans Against the War, or said that the Communist leaders had ever considered giving up on the war."

I understand that there is a 1985 memoir by Truong Nhu Tang (A Vietcong Memoir) that mentions the U.S. anti-war movement (thanks to Richard Jensen's online bibliography. It is possible that while the author, memoir and year are all wrong, the quotation may yet be authentic and merely misattributed.

As to the implications of such a link between Vietnam-era protesters and those agitated by the current situation in the world, it seems to me that the use of the quotation, inaccurately or not, is more about firing up conservatives, particularly those of Vietnam-era age, against John Kerry than about attacking those who are "anti-war protesters" (an ambiguous term) today.