Открывающее глаза:Until 15th August 1971, the US dollar was backed by gold. The US was fighting the Vietnam war and spent all the gold paying for the war. Nixon broke the link between the dollar and gold because they couldn't pay the bills in gold any more, they didn't have any.
http://en.wikipedia.org/wiki/Nixon_Shock [wikipedia.org]
The dollar was then simply being printed, unbacked by anything. This increases the supply of dollars and the value falls massively. Huge inflation.
1972-3 Nixon or someone went to the Saudis and "persuaded" them somehow to remain only US dollars in return for oil. No idea what they promised, but it was big. From that point, the US dollar is pretty much backed by OPEC oil. It was denominated in dollars before, but the dollar had been backed by gold, so basically the oil price was based on gold. Not so after 1971.
So. All oil all over the world has to be bought in US dollars... The demand for US dollars (not gold) rockets, all the central banks across the world have to keep reserves on hand so the countries can buy oil. Billions of them. Trillions in total.
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