Final answer:
The balance of power between the United States national government and state governments is shaped by the Constitution and Supreme Court rulings. The Supremacy Clause establishes the supremacy of the Constitution and national laws over state laws. The Tenth Amendment reserves powers not delegated to the federal government to the states or the people.
Step-by-step explanation:
The balance of power between the United States national government and state governments is shaped by the Constitution and Supreme Court rulings. The Supremacy Clause, found in Article VI of the Constitution, establishes that the Constitution, national laws, and national treaties are the supreme law of the land. It states that judges in every state must obey the Constitution, even if it contradicts state laws. This provision ensures that national laws take precedence over state laws in cases of conflict.
The Tenth Amendment, on the other hand, is found within the Bill of Rights and guarantees that powers not delegated to the national government are reserved to the states or the people. This means that any powers not specifically granted to the federal government by the Constitution are retained by the states.