“There is no use either in cherishing illusions as to the practical consequences of a system in which political power and control of economic production and distribution are irrevocably delegated to, or conferred upon, the same persons. In so far as the state absorbs and distributes a larger and larger portion of the public wealth, the leaders of the ruling class come to possess greater and greater facilities for influencing and commanding their subordinates, and more and more easily evade control by anybody.”