Pete Seeger, the singer and song collector who spearheaded an American folk revival,  died Monday.  Seeger  spent a long career championing folk music as both a vital heritage and a catalyst for social change. He sang topical songs and children’s songs, humorous tunes and earnest anthems.  He did much create an interest in our traditional music and to encourage a new generation of performers to carry it on.    He also belived in music as a form of community.  He always encouraged listeners to join in and sang for the labor movement in the 1940s, civil rights marches in the 1960s, anti-war rallies in the 1970s,  environmental causes in the 1980s and 90s, and for the occupy movement in the 00s.