Oddly, I don't see it that way.... re: Liberalism and Totalinarianism. I had a lot of left-wing classmates in college (card-carrying communists, actually) and I can still tell the difference.
Liberalism touts equal rights, freedom of speech and equal opportunity. The idea is not to bring down the rich, but to afford all, rich or poor, equal opportunities and avenues of development, both social and economic.
Communism touts complete equality by the removal of the right to own property. In communism, personal wealth is an anathema. Soomething that should not happen. It absolutely removes your right to wealth but assures you will never starve.
Unfortunately, in practice, this means that a Communism very easily turns into a totalitarian state. The state holds all the rights to everything, and no dissension in ideologies are possible.
Liberalism, on the other hand, touts freedom as one of its ideals. While it may still tax people more than a conservative policy in order to fund social programs geared to ensure freedom from want, it does not deny people the right to become wealthy.
And it's still not as taxing as socialism... and a truly far cry from communism and totalitarianism. You've got to keep them all straight...
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As for how it all applies in practice... God only knows. Political realities and the need to court voters means that the words "Liberal" and "Conservative" apply to "Democrat" and "Republican" in the sense that they're only "Liberal" and "Conservative" in relation to each other, and each party makes concessions to social realities in order to maintain their support base and not alienate swing votes.