Federalism Versus Unitary Systems

The excerpt highlights which of the following as an advantage of a federal system over a unitary system?

In my reflections on the organization of government, I have come to believe that a union of states requires a delicate balance of power. A federal system, while allowing for local autonomy, also ensures that a strong central authority can coordinate common interests. It is imperative, however, that the diversity of regional identities is recognized and preserved. The unitary system, by its nature, centralizes decision-making, which can lead to efficiency but may undermine local traditions and preferences. I find that the federal model fosters both innovation and accountability by dividing responsibilities appropriately. Ultimately, the success of a political system depends on its ability to integrate the varied interests of its constituents. – James Madison, Federalist Reflections, 1788