A document written just after the SNP push, obtained through the Freedom of Information Act in 2005, reveals that British leaders were long aware of how lucrative the North Sea oil would prove to be. The document, prepared by Scottish economist Gavin McCrone and presented to cabinet officials in the mid-1970s, said that if the oil profits were directed to an independent Scotland, its currency "would become the hardest in Europe, with the exception perhaps of the Norwegian Kronor." Instead, the British government retained control of the North Sea venture, and the paper languished for 30 years.
Above, ships dock in the harbor in Aberdeen, Scotland, in June, 2008. The harbor is the busiest in Britain, transporting goods to the North Sea oil platforms.