There is enormous inertia -- a tyranny of the status quo -- in private and especially governmental arrangements. Only a crisis -- actual or perceived -- produces real change. When that crisis occurs, the actions that are taken depend on the ideas that are lying around. That, I believe, is our basic function: to develop alternatives to existing policies, to keep them alive and available until the politically impossible becomes politically inevitable.
-- Milton Friedman (1912-2006), American economist, Capitalism and Freedom (1962), Preface