Legal Realism, Critical Legal Studies (CLS), Postmodernism (PoMo), and Marxism are all intertwined, somehow. This article sees Marxist currents as the common thread throughout U.S. left legal theory. Marxism as an ideology never took off in the United States, outside of law schools. But there, Marxism seems to have overtly or covertly informed these three legal theories, resulting in what in Marxist terms are revisionist, deviationist, and sub-reformist lines. Whether one is in favour of or opposed to the extrapolations in the U.S. from some portions of Marxism into legal theory, it is worth examining Legal Realism, CLS and PoMo from the perspective of Marxism to see how these extrapolations in fact have played out, or how they may. This article concludes that Legal Realism did not “follow through” on its radical origins, that CLS stayed radical but never took state power, and that PoMo is too open textured to be at all useful as a tool to fight against oppression or exploitation.