Still, the danger of the practice of violence, even if it moves consciously within a non-extremist framework of short-term goals, will always be that the means overwhelm the end. If goals are not achieved rapidly, the result will not merely be defeat but the introduction of the practice of violence into the whole body politic. Action is irreversible, and a return to the status quo in case of defeat is always unlikely. The practice of violence, like all action, changes the world, but the most probable change is a more violent world.
Hannah Arendt (1906-1975) German-American philosopher, political theorist
“Reflections on Violence,” New York Review of Books (27 Feb 1969)
(Source)