Oil anchors world financial markets, and Opec has just decided to raise its anchor. The consequences could be profound, and go far beyond the power game between the traditional oil producers in the Middle East and the new generation of shale producers in North America.

Oil, it is true, is less important than it was. Steady improvement in technology has rendered the developed economies less “oil-intense”, and less vulnerable to a repeat of the 1970s, when oil price spikes twice led to savage recessions.

But ever since the postwar version of the gold standard ended in 1971, with President Richard Nixon’s decision to end the dollar’s fixed price in gold, oil has been its closest replacement as a store of value in the world economy. In the 1970s, the savage oil price spikes in terms of dollars, engineered by a far more active Opec, merely restored oil’s value in terms of gold. US economic pump-priming had weakened the dollar.