Classical liberalism as it is known to the west differs from and is prior to the rise of the left. The left is Marxist while classical liberalism followed Jesus Christ, Adam Smith and free enterprise capitalism for individuals.
Individual freedom and self-directed independence within a nation of free individuals without a legally superior class over them required millenia to develop. The left, and Karl Marx, saw only the hard side of English industrial capitalism with workers thrown off rural farmland and into dirty, dank, polluted factories with long hours, low pay and a vast difference between the poor and rich company owners. The urban struggle for a humane standard of living and work conditions required a couple of centuries to develop in the west. Marxist philosophy and the communist manifesto developed during that period. It was entirely unAmerican and neo-Hegelian.
Karl Marx formalized a theoretical account for human social evolution that was based on conflict and dialectical progress or evolution. Over the 19th and 20th centuries the left added whatever new idea they could to their platform, such as atheism and evolution, as a hardening of their front against capitalism.
Anti-capitalists of the Marxist variety had little experience of the United States and its foundation upon classical liberalism with properties of rights for individuals to be free from adverse interference by the state. Instead they viewed history through the neo-Hegelian evolutionary dialectical lens of class conflict. For quite a lengthy period the United States was made mostly of rural farming people. With industrialization and the rise of a consumer culture people quite farm labor and moved to cities. The American south after the civil war saw quite a number of free former slaves moving north for their own new deal (before FDR’s).
The integration movements in American 20th century culture were piggybacked with anti-capitalist socialist agitators. People like Bernie Sanders were first arrested for protesting against negro discriminatory policies not uncommonly, before any socialist agitation. Anti-war policies in the 1960s and the new left were existential-dialectical neo-utopians disinterested in the military industrial complex. Following TImothy Leary’s maxim they turned on, tuned, in and dropped out. The new left had pacific sentiments without much regard for classical liberalism which they had lost sight of in the midst of white collar conservative, big business, IBM computer, capitalist, big banked urbanism.
With the development of fast transistor chips society and communications went through several economic qualitative technological upgrades. The left were as drawn to computers as formerly were the management corp. The left saw capitalism and big business rather than free enterprise and individualism. The left regarded themselves as individualists and the urban blue collar and white collar workers as tools for the machine, the matrix etc.
Presently the left is without a solid understanding of capitalism, free enterprise or history. As an identity movement of women, homosexuals, and internal proletariats such as Hispanics, the left simply wishes to move in and take over. Socializing business from the top down. Ossifying business at a level of Marxist synthesis for a Corporatism political philosophy including the left, brings the dictatorship of the proletariat into being and eliminates individual sovereignty as the foundation of the United States of America.
Fundamentally the left as an opposition party is incompetent and unable to reform capitalism and free enterprise without socialism (or with it either). The left has no ability to comprehend ecological economics and merge it into free market practices. The left has largely killed the Democrat Party as an opposition party to Republican who are oriented toward allowing the concentration of wealth.
The left cannot bring itself to shed its Marxist orientation and simply study how to make a democracy work effectively for the well-being of all citizens. Leaving no one behind, a contemporary democracy would not hinder individuals from inventing and upgrading personal, private and public sectors investments.
Democracy has all of the tools it needs to reform economic methods and to make them consistent with a healthy ecosystem. There is no need of socialism or communist dictatorship to rectify Adam Smith’s outlook with modern reality. If the left are the Democrat Party and they have abandoned capitalism and finding its limits and capacities for making ordinary life better and survivable ecospherically, they are displacing new party formations with time consuming spoilt political philosophy. If Donald Trump was knowledgeable about ecological economics he would get 25% more votes in the next election. He is not all bad.