From The Nation:
He made it clear in his plays and his essays that his critical thinking and social consciousness had their genesis in the red politics that were pervasive when he was growing up, a politics catalyzed by the suffering he witnessed and experienced in the Great Depression, a politics shaped in response to the toxic, obnoxious valorization of greed always, always re-emerging in American history as a bedrock tenet of the political right. Although he refused the mechanical determinism of the unthinking Marxist left, he created in his greatest play a drama in which it is impossible to avoid thinking about economics–money–in any attempt to render coherent the human tragedy unfolding before you.
Consider the Lomans: What has brought darkness down upon this family? Their flaws are part of their tragedy, but only a part–every flaw is magnified, distorted, made fatal by, well, alienation, by the market, where the pressure is inhuman and the human is expendable. Consider the moment when the Nothing of tragedy is enunciated, and annunciated, in Death of a Salesman, Biff and Willy’s final fight (“Pop, I’m nothing! I’m nothing, Pop! Can’t you understand that? There’s no spite in it anymore. I’m just what I am, that’s all. Will you let me go, for Christ’s sake?”). It’s tragic negation, vast and shatteringly intimate; everything is annihilated, and at the same time something new is being born. It’s “nothing” of the tragedies of Euripides and Shakespeare, and in Miller’s postwar, marketplace masterpiece, one hears an echo of another “nothing,” tragic but also political–namely, “You have nothing to lose but your chains.”