Political philosophy seems often to reside at a distance from the world. Principles are one thing, politics another, and even our best efforts to live up to our ideals seldom fully succeed.
The Second World War supplied the occasion for the spending, and Keynesian economics supplied the rationale. But Keynesian fiscal policy had political appeal even before the war demonstrated its economic success. For unlike the various proposals for structural reform, such as vigorous antitrust action or national economic planning, Keynesian economics offered a way for the government to control the economy without having to choose among controversial views of the good society. Where earlier reformers had sought economic arrangements that would cultivate, citizens of a certain kind, Keynesians undertook no formative mission; they proposed simply to accept existing consumer preferences and to regulate the economy by manipulating aggregate demand.
Unlike the liberty of the early republic, the modern version permits — in fact even requires — concentrated power.