No it's not. Any form of government is an attempt at centralization of resources and decisions. It is an attempt to move closer to an extreme system of singular decisions with a single point of resources. You do tend to see these concentrated centralized structures within government. Leaders, central banks, executive branch, centralized resources.... etc. Although It's not fully centralized, the creation of government from no government is essentially movement in the direction of centralization. So in other words:

The point of government IS centralization. The US government is sort of an attempt at centralization with checks and balances. An attempt to make sure that the centralization doesn't become too powerful. A movement towards the extreme but not all the way.