Once upon a time, in what many people now reminisce about as “the good old days,” there were just two reigning ideologies: capitalism and communism. Capitalists believed in the sanctity of private property rights, the magic ability of money to be the measure of all things, and in the mystical invisible hand of the marketplace for finding optimal solutions to economic problems. Communists believed in the power of communal property, the ability of rational, objective scientific methods to be the measure all things, and in the power of central planning for finding optimal solutions to economic problems. Both of them fail, eventually, and have done so at various times. Capitalism’s great failure was the Great Depression; communism’s great failure was the collapse of the USSR.
There are some patterns within this general framework of failure. When communism fails (as in the USSR, and, in economic rather than in political terms, in China, Vietnam and elsewhere) it reverts to capitalism (while trying to retain a few communist elements). And when capitalism fails, the capitalists go to war, and the result is fascism.