We believe half-instinctively that evil always defeats itself in the long run. Pacifism is founded largely on this belief. Don't resist evil, and it will somehow destroy itself. But why should it? What evidence is there that it does... unless conquered from the outside by military force?

The Collected Essays, Journalism, and Letters of George Orwell: My country right or left, 1940-1943 (ed. 1968)