What is sovereignty?
Britannica: . . . the ultimate overseer, or authority, in the decision-making process of the state and in the maintenance of order.
What is popular sovereignty?
Wikipedia: Popular sovereignty is the principle that the authority of a state and its government are created and sustained by the consent of its people, who are the source of all political power. Popular sovereignty, being a principle, does not imply any particular political implementation.[a] Benjamin Franklin expressed the concept when he wrote that "In free governments, the rulers are the servants and the people their superiors and sovereigns".
What is dual sovereignty?
LII - Dual Sovereignty Doctrine: where there are two sovereigns, there are two laws.
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Tribal Sovereignty: Tribal sovereignty in the United States is the concept of the inherent authority of indigenous tribes to govern themselves within the borders of the United States.
Originally, the U.S. federal government recognized American Indian tribes as independent nations, and came to policy agreements with them via treaties. As the U.S. accelerated its westward expansion, internal political pressure grew for "Indian removal", but the pace of treaty-making grew nevertheless. The Civil War forged the U.S. into a more centralized and nationalistic country, fueling a "full bore assault on tribal culture and institutions", and pressure for Native Americans to assimilate.[3] In the Indian Appropriations Act of 1871, Congress prohibited any future treaties. This move was steadfastly opposed by Native Americans.[3]
Currently, the U.S. recognizes tribal nations as "domestic dependent nations"[4] and uses its own legal system to define the relationship between the federal, state, and tribal governments.
From NCSL: An Issue of Sovereignty: Tribal sovereignty refers to the right of American Indians and Alaska Natives to govern themselves. The U.S. Constitution recognizes Indian tribes as distinct governments and they have, with a few exceptions, the same powers as federal and state governments to regulate their internal affairs. Sovereignty for tribes includes the right to establish their own form of government, determine membership requirements, enact legislation and establish law enforcement and court systems.
