The term Sovereign Citizen is an oxymoron. A sovereign is simply an entity capable of making its own decisions. As in not requiring another to think for it. A citizen is an entity that is completely subject to another entity's rules with no say in the matter.

The United States was meant from the beginning to be a nation of sovereigns as the government was meant to operate with the consent of the governed. The Sovereign Citizen movement was deliberately created to confuse this issue and make people forget what consent of the governed really means.