Liberalism is a political philosophy that emerged as feudal political structure started to strain with the growth of mercantilism. Merchants wanted the wealth they were hoarding to translate into power, but they couldn't buy power because power was tied to land and land was tied to nobility which was entirely determined by the unitary sovereign which was entirely determined by heredity.

Merchants wanted their wealth to translate to power, so they developed a new political theory for where power should come from - private property. Private property was to be the basis for all political power and political power was not to impinge on the power of wealth unnecessarily. Liberalism was focused foundationally on ending the power of the sovereign to that merchants could buy and sell land, build privately-run cities, own and breed slaves for sale...

... and then they realized that they needed a way to do it to brown people who were too numerous to just kidnap. So they started to invent abstract concepts to disconnect power from reality so they could reassign power. They invented the concept of abstract rights, and they put a right to private property into a list of things like the right to print whatever they wanted in newspapers that they owned and the right to buy and sell anything.

Liberalism invents this concept of private property and then invents a rule that states that if you apply labor to land then you get private property rights to it. This was great because they could claim that indigenous people weren't working the land and all the European merchants had to do was chop down some trees and put up a fence and now they had an "inalienable right" of private property.

And then they needed a solution to every merchant raising a military to become warlords and destroy the wealth of others, so they landed on the democratic republic form as a mechanism to resolve conflicts between the wealthy in a way that didn't require war.

Liberalism is the political philosophy of merchants and land owners that gives them political power on the basis of their effectiveness at accumulating wealth and makes the bare minimum concessions to the laboring masses required to get them to fight against the kings on behalf of the merchants.

It is the political philosophy of settler colonialism, of privatization, of chattel slavery, of Thomas Jefferson's breeding plantations, of Coca Cola hiring death squads, of the Opium Wars, of killing all the buffalo so that land could be taken from the Lakota, of getting people addicted to drugs in order to get them into debt.

Liberalism is the political movement that destroyed the social safety net that feudal societies maintained through nobilesse oblige and impoverished the masses everywhere until it forced the emergence of a labor movement and the creation of labor unions to give the masses a vehicle to fight the liberals, which the liberals crushed with military and paramilitary violence.

A faction of Liberals developed a theory of progressivism that they thought could appease the labor movement and maintain liberalism. But traditional Liberals chafed at the idea of the government doing anything to help the masses, because they believed if people wanted a better life they should just work harder for the Liberals with money and land. So factions within Liberalism fought and continue to fight in the best way to express Liberalism.