Final answer:
The Tenth Amendment under cooperative federalism has been interpreted as confirming that powers not delegated to the national government are reserved for the states, leading to a cooperative relationship where both levels of government jointly address national issues, thus eroding strict jurisdictional boundaries and emphasizing state sovereignty.
Step-by-step explanation:
Under cooperative federalism, the Tenth Amendment has been interpreted as an expression of the distinction between the powers of the federal government and the states. Rather than significantly curtailing the federal government's powers, it serves to reiterate the notion that what is not specifically delegated to the federal government or prohibited by it for the states remains within the states' purview. This recognition has led to cooperative efforts where both state and federal governments work jointly to address national issues, such as during the Great Depression and the civil rights era.
During this era, cooperative federalism facilitated the increased involvement of the national government in areas traditionally managed by the states, through the use of grants and mandates, thus blurring the boundaries of state and federal jurisdictions. This blend of state and federal roles is depicted metaphorically as a marble cake, signifying the intertwined responsibilities in policy areas.
The Tenth Amendment serves as a reminder of state sovereignty under the Constitution, emphasizing that powers not granted to the federal government are reserved for the states. This plays a fundamental role in shaping the dynamic balance between national power and state power within the U.S. federal system.