Who advocated violence to protect the revolution?

Leon Trotsky, a key figure in the Russian Revolution, advocated for the use of violence to protect and advance the revolution, particularly through the idea of "permanent revolution." He believed that revolutions needed to be defended against counter-revolutionary forces and that revolutionary violence was sometimes necessary to achieve socialist goals. His thoughts on the subject were influential in the early years of the Soviet Union, particularly in the context of the Civil War and the formation of the Red Army.