I like what the guy said in the video. That we have a federalist form of government, but where the Federal Government is part of that system, but not the only government. That we don’t have a unitary government that is common in Britain, Egypt and perhaps Russia. Where so much power is centralized with one central authority. And you have states or provinces, but really only in name only, but not without much authority over their own affairs.
In the American form of government the Federal Government is obviously part of that. But our states and localities are real as well with real power over their own affairs. With the ability to govern themselves, with the Feds being able to aid with federal funding. But the Federal Government is mainly there to handle national affairs. Like national security, foreign policy, terrorism, interstate crimes, regulating interstate commerce.
Interstate infrastructure would be another good role for the Federal Government, but where the states have the authority to manage what happens inside their own borders just as long as they are within the United States Constitution. With the Federal Government handling the issues that effect the whole country like as it deals with interstate crime and terrorism. And interstate commerce.