I guess that seems to be the underlying difference between libertarianism and socialism. Libertarianism is built on the idea that people are inherently bad and that prosperity only comes from winners defeating losers. Socialism posits, and in fact requires, that we can rise above being afraid of one another, and work together. Libertarians often seem to take the position that this default position of selfishness is a given, without realizing what kind of a miserable world we would live in if it were true. They fight endlessly for the notion that helping others must be voluntary, without understanding that the right they are fighting for is the right to not help others.
Human beings are not selfish, terrified, petty little creatures. We are so much more. Our greatest accomplishments come not from fear, or self-interest, but from love.
Noam sums it up pretty well. He talks about business feudalism, which is exactly how it works. A wealthy owner now is just like a duke or an earl was in the dark ages. And the rest of us are consigned to a state of serfdom, toiling our lives away, receiving a tiny portion of the benefits of our labor. Breaking away from monarchy and aristocracy took government away from that system, but in the last two centuries, we replaced it with business instead. Socialism is nothing more than applying the democratic principals that made the United States stand out in the world to the sphere of business. Our collective production should benefit us all, not just the parasites (to take a term from TD and apply it in a way that's accurate) whose only contribution is to sign their names to dotted lines and trade pieces of the pie back and forth.
A representative government, by, for, and of the people took power from the few and entrusted it in the hands of the many, to work for the benefit of all. Representative business should do the same. Anyone can see the astounding ways that wealth is used to circumvent the democratic process. Rich companies and the wealthy elite who own them hire legions of lobbyists and lawyers, and control who does or does not get elected. Their wealth buys up the democratic process. By not taking the reins of business from the few and gearing it towards the benefit of all, we are giving up the very core of American ideals and allowing ourselves to slip back into feudalism. The extension of social Darwinism that is used to justify this massive disparity, that some people are just naturally more apt to succeed and everyone else is a failure... that sounds a lot like the invocation of divine right to me.