They took control using violence in the 1920s , and it became one of the major bases in the labor movement .
Radical union organizers , including Communists , played a role in the union from its early years .
union organizers took control using violence in the 1920s , and it became one of the major bases in the labor movement .
Radical union organizers , including Communists , played a role in the union from its early years .