Keynesians were initially mystified by this dramatic breakdown in the supposedly stable and manageable relationship between growth (or employment) and inflation. Their models said it couldn’t happen, so they looked for an explanation to deflect mounting criticism and soon found one: The economy had been hit by a ‘shock’, namely sharply higher oil prices! Never mind that the sharp rise in oil prices followed the breakdown of Bretton-Woods and devaluation of the dollar: This brazen reversal of cause and effect was too politically convenient to ignore. Politicians could blame OPEC for the stagflation, rather than their own policies. But an objective look at history tells a far different story, that the great stagflation was in fact the culmination of years of Keynesian economic policies. To generalise and to paraphrase Friedman, stagflation is, always and everywhere, a Keynesian phenomenon.
– John Butler, on the Cobden Centre website.