That men do not learn very much from the lessons of history is the most important of all the lessons that history has to teach. Si vis pacem, the Romans liked to say, para bellum–if you want peace prepare for war. For the last few thousand years the rulers of all the world’s empires, kingdoms and republics have acted upon this maxim–with the result that every civilised nation has spent about half of every century of its existence waging war with its neighbours. But has mankind learned this lesson of history? The answer is emphatically in the negative. Si vis pacem, para bellum still is the watchword of every sovereign state.
– Aldous Huxley, “A Case of Voluntary Ignorance” Collected Essays (1958)