The oil cartel has been weakened by non-cartel producers and alternative energy sources such as shale
A cursory glance at the history of the oil price since the second world war tells its own story. There are booms when the price of oil is low and busts when the cost of crude rises. Four spikes in oil since 1973 have been matched by four recessions over the same period.
The so-called postwar golden age is also the story of a flatlining oil price, which remained at around $2 a barrel during that period. Five Middle Eastern nations formed the Organisation of the Petroleum Exporting Countries in 1960 but it was more than a decade before Opec bared its teeth.