Final answer:
The doctrine in question is known as dual federalism, where state and national governments have authority in separate and distinct realms. The Supreme Court has historically ensured proper adherence to this division, delineating the balance of power within the U.S. Constitution's framework of federalism.
Step-by-step explanation:
The doctrine that the national government and state governments operate in almost totally separate spheres is called dual federalism. This style of federalism suggests that the states and national government have exclusive authority in distinctly delineated spheres of jurisdiction, much like the distinct layers of a layer cake. During the period of dual federalism, the Supreme Court played a crucial role in upholding this division of power, ensuring that neither the states nor the national government overstepped their constitutional boundaries. This structure of governance is a result of the U.S. Constitution which has led to a unique form of federalism in the United States. The American system divides sovereignty and grants both national and state governments the capacity to act directly upon the citizens.
Through various stages of American history, the relationship between state and federal government has evolved. This evolution is marked by periods such as new federalism, which advocated for the decentralization of policies, and immigration federalism, reflecting a gradual increase in state influence over immigration matters. These shifts in federalism reflect the changing attitudes of government officials, public demands, and judicial interpretations.