Karl Marx and modern Lefties are dealing with a problem that disappeared, in many parts of the world, without their even noticing it.
They are responding to a condition of life and political conditions that precede the founding of the United States.
Marx and the modern Left were concerned that the emerging industrial commercial world would allocate all of its resources and profitability to the existing hereditary upper class and leave the rest of the society pretty much the way it was.
The modern Left continues to believe in these very same concepts. The president of the United States, who is an extreme Leftist, constantly harps on the upper 1% of the society having disproportionate wealth and power.
There are two things that have completely destroyed the Marxist idea and basic Leftist principles... and those people have no idea what it is.
First and foremost, modern commerce has been so extraordinarily productive as to completely change society. It has given us modernity that can be contrasted with what life is like in Damascus today. Modern commerce gives us very long lives, good health, widespread prosperity, extraordinary travel opportunities and incredible ability to develop our individual uniqueness in art and other talents. It gives us vast areas of the world that are peaceful and safe.
Second, America with its enormous open territories provided new life for the oppressed serfs of Europe. It provided an escape from the hereditary elites. Revolution wasn't necessary.
American both in its development of an egalitarian democracy and its development of a unique nationhood idea offers an alternative to Marxism and Leftism. Democracy in a commercial society has totally demolished the validity of the ideas of Marx and the Left.
The Left is trying to create a better person, a revolutionary person, on a vast scale using a central government. Think China and Mao. They are wrong. The Left is completely blind to the fact that commerce is now creating the most unique extraordinary individuals with their talents developed and expanded in a way that no one has ever conceived in the history of mankind.
Both Marxists and the Left are looking backwards to a world that doesn't exist in the modern commercial America.