
Everyone needs to remember that the "United States" is a foreign entity.
It's only relationship to the united States of America is as a subcontractor
obligated to provide certain enumerated government services for the states in
common.
With respect to the united States of America, the United States only
exercises delegated power and has no power of its own.
Yet, it does have its own bits of land used to complete its duties and it
does have its own citizens--- those born in Washington, DC., members of the
military, the federal civil service, those born in Territorial and Insular
states, and so on.