In any revolution, its internal causes are fundamental and its external ones are supplementary. - Mao Zedong

历史上的战争分为两类，一类是正义的，一类是非正义的。一切进步的战争都是正义的，一切阻碍进步的战争都是非正义的。我们共产党人反对一切阻碍进步的非正义的战争，但是不反对进步的正义的战争。对于后一类战争，我们共产党人不但不反对，而且积极地参加。前一类战争，例如第一次世界大战，双方都是为着帝国主义利益而战，所以全世界的共产党人坚决地反对那一次战争。反对的方法，在战争未爆发前，极力阻止其爆发；既爆发后，只要有可能，就用战争反对战争，用正义战争反对非正义战争。

革命不是請客吃飯，不是做文章，不是繪畫繡花，不能那樣雅致，那樣從容不迫，文質彬彬，那樣溫良恭儉讓。革命是暴動，是一個階級推翻一個階級的暴烈的行動。

Between war and peace, the possibility of peace is greater. Currently the possibility of peace is greater than in the past. The strength of the socialist camp is greater than the past and the possibility of peace is greater than at the time of World War II. The Soviet Union is powerful and the national independence movement is our strong ally. The Western nations are not stable. The working class, a part of the bourgeoisie and the American people do not want war; therefore, the possibility of peace is greater than that of war. Nevertheless, there is also the possibility of war. There are the maniacs and imperialism wants to extricate itself from economic crises. The duration of atomic warfare today will be short, three instead of four years. We must be prepared. What should be done if war really comes? I want to discuss this problem. If there is war, we will fight. Let imperialism be swept clean and we will start construction again. Thereafter there will not be any more world war. Since a world war is possible, we must prepare for it. We must not spend our time napping. Do not be alarmed either if there should be war. It would merely mean getting people killed and we’ve seen people killed in war. Eliminating half of the population occurred several times in China’s history. The 50 million population in the time of Emperor Wu in the Han Dynasty was reduced to 10 million by the time of the Three Kingdoms, the two Chin Dynasties and the North and South Dynasties. The war lasted for decades and intermittently for several hundred years, from the Three Kingdoms to the North and South Dynasties. The Tang Dynasty began with a population of 20 million and did not reach 50 million until Emperor Xuan. And Lushan staged a revolt, and the country was divided into many states. It was not reunited until the Song Dynasty, some 100 or 200 years later, with a population of just over 10 million. I once discussed this with XX. I maintained that modern weapons were not as powerful as the big sword of China’s Guan Yunchang, but he did not agree with me. Not very many people were killed in the two World Wars, 10 million in the first and 20 million in the second, but we had 40 million killed in one war. So, how destructive were the big swords! We have no experience in atomic war. So, how many will be killed cannot be known. The best outcome may be that only half of the population is left and the second best may be only one-third. When 900 million are left out of 2.9 billion, several five-year plans can be developed for the total elimination of capitalism and for permanent peace. It is not a bad thing.