The Left is in complete collapse because the working class has awakened to the Left's betrayal and abandonment of the working class in favor of building personal wealth and power.
The source of the angry angst rippling through the Democratic Party's progressive camp is not President Trump--it's the complete collapse of the Left globally.Broadly speaking, the Left favored labor (whose rights were protected by the state) and the Right favored capital (also protected by the state)
But over the past 25 years of globalized neoliberalism, social democratic movements have abandoned labor to embrace the self-serving wealth and power offered by capital. The essence of globalization is: labor is commoditized as mobile capital is free to roam the globe for the lowest cost labor. In contrast, labor is far less mobile, and unable to shift as fluidly and frictionlessly as capital to exploit scarcities and opportunities.
Neoliberalism--the opening of markets and borders--enables capital to effortlessly crush labor. The social democrats, in embracing open borders, have institutionalized an open immigration that shreds the scarcity value of domestic labor in favor of lower cost immigrant labor that serves capital's desire for lower costs.
Globalization and neoliberal financial / immigration policies signify the collapse of the Left and the victory of capital. Now capital completely dominates the state and its cronyist structures--political parties, lobbying, campaign contributions, charitable foundations operating as pay-for-play cash vacuums, and all the other features of cartel-state capitalism.
To mask the collapse of the Left's economic defense of labor, the Left's apologists and PR machine have substituted social justice movements for economic opportunities to acquire economic security and capital. This has succeeded brilliantly, as tens of millions of self-described "progressives" completely bought the left's Great Con that "social justice" campaigns on behalf of marginalized social groups were the defining feature of Progressive Social Democratic movements.
This diversionary sleight-of-hand embrace of economically neutered "social justice" campaigns masked the fact that social democratic parties everywhere have thrown labor into the churning propellers of globalization, open immigration and neoliberal financial policies--all of which benefit mobile capital, which has engorged itself on the abandonment of labor by the Left.
 via from Zero Hedge