Macroeconomics needs to focus on managing abundance and not scarcity

Macroeconomic theory has to be constructed around this now, not the old Keynesian identity which took deficiency as its starting point

Macroeconomics as a formal part of economics is less than a 100 years old. The economy viewed as a whole became a subject of systematic study only after the Great Depression of 1929-37.

The increased appeal of communism from the Soviet Union was a major catalyst. Until the Great Depression, economists thought all markets would adjust automatically. And they would have, too, given time as indeed they used to. But no one knew how much time it would take.

So Franklin Roosevelt in the US and Adolf Hitler in Germany, independently decided that the government would help the markets adjust.