Here, from Arthur Dahlberg's wonderful Jobs, Machines, and Capitalism (Macmillan: 1932), p. 89, is a chart showing the wealth-centrifuging effect of the First World War. Dahlberg cites the National Bureau of Economic Research, Income in the United States (New York, 1922), pp. 115-16.
|Year||Total Individuals Income||Income of Top 5%||= % of Total Income|
Notice the wealthy's percentage starts dropping as soon as war is declared in 1917 and continues into 1919 even though the War ended in late 1918.
Notice also that extreme wealth concentration literally stifles even the wealthy because the whole pie grows so fast when wealth is centrifuged that the wealthy's 33% share in 1913 is only two thirds of their "paltry" 24% share in 1919.
Eventually we'll get the figures for World War II also. Meanwhile, we repeat what we said above -