With the acceleration of inflation in the post-pandemic recovery, the debate seemed to be limited to whether the inflationary spike would be short-lived or persistent and become imbedded into inflationary expectations. While some Keynesian authors like Paul Krugman initially believed that inflation was caused by cost-push factors including by the sharp rises in energy and foodstuff prices as a result of the Ukraine war, and that it would quickly subside, the debate shifted rapidly and a new consensus according to which inflation was, in part the result of over stimulation of demand during the pandemic coupled with supply side shocks that lowered the potential level of output which provides the main theoretical justification for raising interest rates. Thus, even when most authors accept the notion that snags in the supply chain played a role in the acceleration of inflation, the main cause is to be seen on the excess demand side with the economy beyond its potential output level.
The challenge to conventional wisdom, and its emphasis on demand, has come from left
of center authors, like Robert Reich, that suggest inflation is caused by greedy corporations that have increased their profit margins during a crisis. This has brought back the old debate about the relationship between administered prices and inflation, and the proposition that inflation is directly related to highly concentrated market structures, or what might be termed oligopolistic inflation.
In other words, there is an ideological divide between those that blame inflation in an incompetent government and central bank reaction to the pandemic versus those that suggest that the real culprits are greedy corporations rising their mark up above their costs.