In the twentieth century oil has been the chief cause of anxiety. In 1914, the United States Bureau of Mines predicted that American oil reserves would last ten years. In 1939 the Department of the Interior said American oil would last thirteen years. Twelve years later it said the oil would last another thirteen years. President Jimmy Carter announced in the 1970s that: ‘We could use up all of the proven reserves of oil in the entire world by the end of the next decade.’
