I think you are mistaking ol' Gene McCarthy for the late Joe McCarthy. ol' Gene was one of the best friends Ho Chi Min ever had.
No, Johnson was the best friend Ho ever had, by lying about the non-existent Gulf of Tonkin attack and by fighting a war so that it could Never be won. (If a high school football team battled the Colts, but the Colts were never allowed to pass the 50 yard line, the high school team would eventually win.) Without invading North Vietnam in response, the war could never be "won."
McCarthy was bright and honest. He was right that wars like Vietnam and Iraq I and II should have been voted on by Congress, as per the Constitution. Add in Clinton's illegal campaign in Bosnia. McCarthy was also the wittiest interviewee I ever saw. He was also a loyal U.S. citizen.