„Who are our enemies? Who are our friends? This is a question of the first importance for the revolution.“
— Mao Zedong Chairman of the Central Committee of the Communist Party of China 1893 - 1976
Chapter 2 https://www.marxists.org/reference/archive/mao/works/red-book/ch02.htm, originally published in Analysis of the Classes in Chinese Society (March 1926), Selected Works, Vol. I, p. 1.