Pete Seeger was always on the right side of history. Or, as The Guardian quoted Lauren Laverne in its obituary on January 28, 2014:
As Lauren Laverne, the BBC6 Music DJ, succinctly put it, it was Seeger's destiny to be "loved and hated by precisely the right people". He was on the side of working people, refugees from fascist regimes, nuclear disarmament and the earth's threatened natural resources, and against segregationists, Stalinists and the military-industrial complex.
On that August day in 1955, as Pete Seeger was being interrogated by the counsel for the House Un-American Activities Committee (HUAC), it was clear that there was not a lot of love for him in that room. He politely told them that his opinions were his opinions, and while they may be different from the opinions of the members of Congress sitting on the committee, he was entitled to hold them and that entitlement was protected by the First Amendment to the Constitution. He, like very few since the Hollywood Ten before him, refused to claim the protections of the Fifth Amendment.
I am not going to answer any questions as to my associations, my philosophical or religious beliefs or my political beliefs, or how I voted in any election or any of these private affairs. I think these are very improper questions for any American to be asked, especially under such compulsion as this.
[...]
I decline to discuss, under compulsion, where I have sung, and who has sung my songs, and who else has sung with me, and the people I have known. I love my country very dearly, and I greatly resent this implication that some of the places that I have sung and some of the people that I have known, and some of my opinions, whether they are religious or philosophical, or I might be a vegetarian, make me any less of an American. I will tell you about my songs, but I am not interested in telling you who wrote them, and I will tell you about my songs, and I am not interested in who listened to them.
He was called before HUAC for his Communist Party membership, which he gave up in 1949 but later admitted he should have done earlier. His work on behalf of unions and peace made him an irresistible target. But interestingly, it was a letter that he wrote in 1942 to the American Legion in California that first brought him to the attention of the FBI, before the Red Scare had properly reached its peak.