How mainstream economists explain (or not) unemployment?

Abstract

One of the tasks assigned to mainstream economists is to legitimize the significance of unemployment. This paper aims to reconstruct the evolution of their approaches from the theoretical impossibility asserted by Pigou to the recognition of involuntary unemployment by Keynes and eventually to different versions of the natural unemployment rate. The unemployment rate had become an instrument for fine-tuning of the economy, but it no longer fulfills this role. It is then the whole dominant macroeconomics that is shaken to its foundations. But this crisis might help to return to expansionary fiscal policies (a Green New Deal) and to the Job Guarantee, thus echoing Keynes' question: "There is work to do; there are men to do it. Why not bring them together?"