As noted in Chapter 14 of A&A, distribution of income among various population groups followed roughly the same patterns in the USA, Sweden, and the former Soviet Union, despite the very different forms of economic organization in each of those countries. Progressives and socialists today claim that if we had a planned economy in which government directed the direction of resources and confiscated money from wealthy people via high taxes, and then re-distributed those monies, that income inequality would be eliminated. Yet, that clearly was not the case in high-tax Sweden and the communist USSR. (In the USSR, the high-income groups tended to be those with membership in the Communist Party, about six percent of the population. Party membership was not easily obtained back then.)
Economically speaking, why would this situation be the case, despite what modern academics, politicians, journalists, and activists are saying today? Please be specific in your answer.