In political science federalism refers to a political system with a constitution that guarantees some range of autonomy and power to both central and decentralized levels of government. That is the federalism in static sense and its principal issue refers to the distribution of sovereignty between the different levels of government in federal states. Instead, federalism in a dynamic sense is a concept of power and it is defined as a federalizing process, in an ongoing evolution depending on centripetal (cooperative federalism) or centrifugal forces (dual federalism). The transformation of the federalist system in the United States after the New Deal is a clear example of it: the principles of welfare state had a great influence on the centr...