From the Wall Street Journal, 3 Aug 1995:
Excerpted here:
Q: Was the American antiwar movement important to Hanoi's victory?
A: It was essential to our strategy. Support of the war from our rear was completely secure while the American rear was vulnerable. Every day our leadership would listen to world news over the radio at 9 a.m. to follow the growth of the American antiwar movement. Visits to Hanoi by people like Jane Fonda, and former Attorney General Ramsey Clark and ministers gave us confidence that we should hold on in the face of battlefield reverses. We were elated when Jane Fonda, wearing a red Vietnamese dress, said at a press conference that she was ashamed of American actions in the war and that she would struggle along with us.
And (regarding Tet '68):
Q: What about the results?
A: Our losses were staggering and a complete surprise;. Giap later told me that Tet had been a military defeat, though we had gained the planned political advantages when Johnson agreed to negotiate and did not run for re-election. The second and third waves in May and September were, in retrospect, mistakes. Our forces in the South were nearly wiped out by all the fighting in 1968. It took us until 1971 to re-establish our presence, but we had to use North Vietnamese troops as local guerrillas. If the American forces had not begun to withdraw under Nixon in 1969, they could have punished us severely. We suffered badly in 1969 and 1970 as it was.