[...] Socialism isn’t only about defending against one’s enemies, against the old world it is opposing; it also has to fight within itself against its own reactionary ferments. A revolution seems monolithic only from a distance; close up it can be compared to a torrent that violently sweeps along both the best and the worst at the same time, and necessarily carries along some real counterrevolutionary currents. It is constrained to pick up the worn weapons of the old regime, and these arms are double-edged. In order to be properly served, it has to be put on guard against its own abuses, its own excesses, its own crimes, its own moments of reaction. It has a vital need of criticism, therefore, of an opposition and of the civic courage of those who are carrying it out. And in this connection, by 1920 we were already well short of the mark.