What's the difference between classical liberalism, modern liberalism, and neo-liberalism?
Classical liberalism involves the original values espoused by the bourgeois revolutionaries of the 18th and 19th centuries, an elevation of liberty and freedom of speech and stuff. Nine times out of ten, advocates aim for a representative political system and a market economy with “little to no government involvement” (i.e. little to no democratic economic presumptions or social welfare reforms that could help tip the scale of power towards labor and away from capital). In this way, it really is the complementary ideology of the capitalist system – an ideology that seeks out “liberty” to the extent that capital can still remain firmly in charge of society. Some people, like Noam Chomsky for instance, believe that the actual logical conclusions of classical liberalism now imply libertarian socialism, since material conditions have changed a good bit since CL’s conception. I’m skeptical of this idea – I think it’s a very capitalist framework. (This isn’t to say that I don’t think a libertarian socialist society shouldn’t champion many of this things classical liberals champion, like freedom from political tyranny and a great respect for the individual. I just think that classical liberalism stops way short of a more holistic conception of “liberty, equality, solidarity” that achieves ACTUAL human liberation, something that libertarian socialism is actually consistent on via economic democracy and the abolition of class domination.)
Modern liberalism generally implies some degree of social liberalism, which in turn is an ideology that takes many of the assumptions of classical liberalism for granted and further argues that greater equality is needed before liberty can be fully utilized. This is why modern liberals/social liberals will generally approve of welfare policies and some concessions for workers’ rights; working- and middle-class social liberals usually support these policies from a genuine perspective to bring about more equality, but upper-class liberals will support them to an extent that capital still remains firmly in charge and class stratification becomes normalized. That latter point is important – nominally about equality, social liberalism is structurally about “reforming so that you can preserve”, essentially passing bigger and better-tasting scraps down to the masses so that they feel more content with their position in life (i.e. still lacking fundamental control at work and in living arrangements, still having to foot colossal bills, but receiving nice benefits and some social prestige).
Neoliberalism is a set of policies and practices that seek out the privatization of economic utilities – a “new liberalism” that essentially just repackages the old ways of pure class domination from capitalists. Neoliberalism took form in the late-70s and early-80s under Reagan and Thatcher and others, and it was mainly a ruling-class response to the 30-year period of social liberalism after World War II. Trickle-down economics, “free trade”, job-outsourcing for cheaper labor, the War on Drugs, etc. – these are all policies that the ruling class pushed to undo any progress being made, especially after the growing revolutionary attitudes of the 1960s. By no means is neoliberalism limited to Republicans; Democrats will happily embrace it, from Bill/Hillary Clinton to Barack Obama. Some say neoliberalism is on its last legs now that Trump and other proto-fascists are gaining power around the world, giving way to a new divide between populists on the left and the right (rather than the old 40-year divide between Whole Foods neoliberalism and 700 Club neoliberalism); I’m not entirely sure about this claim, but my instincts are telling me it might be the case.
Capitalism is now pushing two phenomena that will ultimately lead to its own destruction if we’re sufficiently organized: automation and global climate change. Proto-fascist right-populism can’t address these problems (since it’s merely a front for elite domination), but a socialist left-populism can. Harness the automation for human need/use rather than elite profit, put an end to the unceasing accumulation of capitalism that’s accelerating climate change. All of this taken together might mean that liberalism itself is on its way out. Only time will tell in that regard.
Hope this was informative/answered your question sufficiently!