Marx is clear. He effectively states that the value of a commodity derives from the labor of production. This "value", furthermore, is the only just claim to ownership; what capitalists do, in employing workers, is cheat them of the fruits of their labor. Any profit that they derive is, de facto, the rightful property of those that actually produce, i.e. the proletariat. This contention is key to Marxism, and is the primary justification for the violence advocated in Communist doctrine.One reason that Rand is so despised (and I mean really HATED) within Leftist circles is that she contended that it is entrepreneurship, and not brute labor, that is the "engine of production". Thus, by Marxist theory, it is the capitalists, and no the proletariat, that is justified in the use of force to maintain their rights to ownership. Objectivism literally hamstrings Marxism, by using their own ideological sophistry against them.
In point of fact, value is determined by what one will exchange for a commodity, contentions to the contrary are empirically incorrect, and neither theory practically settles the ethical quandry of ownership, which seems to be more a matter of cultural convention leavened in regards to the distribution of coersive power within that social order. Changes in the distribution of power inevitably lead to all sorts of justification for the thefts and murders that follow; the French revolution was more a matter of the introduction of easily operable firearms and efficient and mobile cannons, rather than a genuine concern fro "brotherhood" or a "class war". Napoleon was the first to master the political use of these new instruments (using cannon, for example, to clear the streets of Paris) - thus, he became the autocratic (and popular) ruler within the resultant chaos. So also Hitler, in Germany (catering to the belligerent anti-Semitism and anger in regards reparations common amogst the German workers) and Stalin (who was able to find the means of motivating the Russian workforce and "dealing" with the perrfidy of the Bolsheviks, all the while remaining true to the intent of Lenin {and Peter the Great, etc.}). Both enjoyed a "popularity" of sorts within their respective states, and both rose to power within the chaos of revolution and social dislocation. All of these despots derived their power from changing military technology, and the resulting change in political power that these developments fostered - NOT, as it is commonly purported by Marxists, by the "rising consciousness" of some economic class or other. "You might not be interested in war, but war is interested in you." Or, as Mao once said, "Power comes from the barrel of a gun".
Or, if you want a free citizenry, pass the guns around. Perhaps the Founding Fathers weren't so elitist after all...
"Doc" Cruel