Pure communism has been tried a few times in America by various Utopian communities, all of which eventually failed. Pure Marxism later attracted, relatively speaking, only a modest body of adherents. And the American Communist party, which was neither purely communist in the old sense nor true to the Marxist ideology, would seem—by the surface statistics, at least—to have been of no great importance either. At no time in its history, for example, did it have more than 80,000 members; it was an apparently ragged and hopeless cause, sometimes harassed but generally tolerated by the generosity of American law. That this was only the visible part of the iceberg many intelligent people long realized, but thousands, indeed millions, did not. How this “party,” in effect an arm of Soviet absolutism, deluded so many liberal-minded people, how it penetrated so deeply and dangerously into the political and intellectual life of the United States, is the burden of the article which begins on the next page, and which concludes, on a most important note, our series on America and Russia.