The the 20th century was an empirical presentation of the data showing that communism was a complete and murderous failure. It could not feed the people who were captured by it.
Another Marxist idea was recently demolished.
The popular Marxist idea that people are primarily motivated by money and self-interest was tested and found empirically false in the 2012 election in which Barack Obama was the winner.
Obama won the election despite the fact that his main support groups, educated youth in their 20s, women, blacks and Latinos had all experienced dramatic reductions in their incomes and job opportunities in the previous four years under Obama's leadership.
The decline in income and job opportunities for these specific groups was far different from that of white males over 30. There was virtually no change in income or job opportunity for the white males during Obama's first four years.
The only conclusion a reasonable person can come to is that voters do not vote self-interest because the self-interest of the groups most harmed by Obama's policies were the groups that voted for him. And in large or larger proportions than in the election four years earlier.
There may be other reasons these people voted against their own interests and experience but that is not the issue. The issue is whether the popular Marxist thesis about financial self-interest being the dominant self-interest of human beings was tested and found false.
My estimate is that somewhere between 20 and 25% of all Americans think about their lives in this Marxist vein. Most other Americans (70-75%) try to explain the world by falling away from 'the old ways'; they usually blame negative outcomes on ignoring tradition ('schools used to be better').