By Neomalthusian:
Modern liberalism's strongest features include:
- favoring progressive taxes as a primary means of promoting relative economic and social equality.
- using the governmental spending power that progressive taxation enables to fund social programs that make life better for people whose goods/services/labor no one wants to buy.
- regulating private sector enterprise to whatever extent necessary to prevent monopolistic pricing, inefficient levels of profit (a.k.a. economic rent-seeking), and consumer fraud and abuse.
- rejecting (often religiously-based) bigoted attitudes toward groups commonly identified as being a racial, ethnic or other minority.
- favoring science, evidence and change over tradition and religion.
A step further, I think the strongest aspects of economic liberalism include:
- understanding monetary sovereignty, i.e. countries that have fiat currencies managed by a central bank do not have to balance their federal budgets the way Aunt Agnes balances her checking account
- recognizing that globalization and technological advancements are causing supply side capitalism to be decreasingly able to raise living standards broadly (i.e. "trickle down")
- but that despite this (the eventual failure of supply side economics' ability to raise living standards broadly being partly attributable to globalization), we should nevertheless openly accept the inevitability of globalization and work with it rather than against it, as global trade and exchange of goods, services and ideas is the most likely to promote global peace and prosperity, versus turning inward and protectionistic.