Why was federalism included in the united sates constitution?

The federalist papers make the case for a federal system in the U.S. This would create a strong central government that is checked by state and local governments. The main idea is that people are inherently fractious and no ones faction should gain complete power.

Also, by allowing different layers of government, people are both involved and also there is a balance of power.

Opposed to the federalism, where people who only wanted states to have power and really no central government. This was refuted by the federalist as causing weakness in countries especially in the foreign affairs.