Why do they call the united state court system a dual system

The framers of the Constitution wanted to create a third branch of the government, equal to the others. This is the federal judiciary. At the same time, they feared overreaching federal power, so they limited the power, or jurisdiction, of the federal courts. This has led to a dual court system, with each having its own key role.

Explanation:

lack of interest from state and local governments.

answer; /// i do believe but not sure(nazi propaganda)//(anti-semitism); ( holocaust) plz check first; ///good luck