That's not the way I remember it.
It was Barry Goldwater who stated: "I would remind you that extremism in the defense of liberty is no vice! And let me remind you also that moderation in the pursuit of justice is no virtue!"
That was an explicit endorsement of the John Birch Society by Goldwater. Levin is full of it.
I'm no "Bircher" but those guys are patriots and were simply demagogued to near death by the MSM of the time when the leftist media was fresh from their triumph in defining "Mcarthyism" and writing it in stone into our history books.
Either your memory is faulty or it is you who is constipated. Google it.
When I attended college many moons ago our Polisci prof stated that one of the greatest propaganda ploys in political history was pulled off by the left when they destroyed the reputation of the birchers.
Republicans have always avoided the hard truth and now we face the result:
Goldwater, the John Birch Society, and Me
William F. Buckley, Jr.
“I think you have clearly stated the problem which Mr. Welchs continued leadership of the John Birch Society poses for sincere conservatives. . . . Mr. Welch is only one man, and I do not believe his views, far removed from reality and common sense as they are, represent the feelings of most members of the John Birch Society. . . . Because of this, I believe the best thing Mr. Welch could do to serve the cause of anti-Communism in the United States would be to resign. . . . We cannot allow the emblem of irresponsibility to attach to the conservative banner.”
- Barry Goldwater -
http://www.commentarymagazine.com/viewarticle.cfm/goldwater—the-john-birch-society—and-me-11248