In which system of government would states function independently of each other?

The answer

States function independently of each other in a confederal system, also called a confederation. In this arrangement, sovereignty rests with the individual states, not the central government. Each state governs itself and cooperates with the others voluntarily. The central authority is deliberately weak: it can only exercise the powers that the member states have agreed to grant it, and it usually depends on the states for funding and enforcement.

Because power flows upward from the states to a limited central body — rather than downward from a strong national government — the states remain the primary, independent units of power. That is exactly what "function independently of each other" describes.

Why the other options are wrong

The usual distractors are the unitary and federal systems. They differ in one crucial dimension: where sovereignty sits.

• Unitary system: All sovereignty is held by a single central government. Regional or local units exist only because the center creates them and can redraw or abolish them at will. States or provinces do not function independently — they are administrative arms of the national government. Examples include France, Japan, and the United Kingdom.
• Federal system: Sovereignty is divided and shared between a national government and the states through a constitution. Both levels act directly on citizens, and neither can simply abolish the other. States have real, protected powers, but they are bound together under a strong central government and are not fully independent. Examples include the United States today, Germany, and India.
• Confederal system: Sovereignty stays with the states, and the central government is subordinate. This is the only arrangement where states genuinely function independently. Examples include the U.S. under the Articles of Confederation (1781–1789), the early Confederate States, and, in a loose modern sense, the European Union and the United Nations.

So unitary concentrates power at the top, federal splits it, and only confederal leaves it at the bottom with the states.

The bigger picture

The key to these questions is to picture a sovereignty spectrum. On one end, the unitary system puts nearly all power in the central government. On the other end, the confederal system puts nearly all power in the member states. The federal system sits in the middle, balancing the two.

History shows why the confederal model tends to be unstable. The United States began as a confederation under the Articles of Confederation, but the central government was so weak — unable to tax, regulate trade, or enforce laws — that the states behaved like independent countries and the system nearly collapsed. This drove the framers to the Constitution and a federal system, which strengthened the center while preserving state powers. Understanding this trade-off explains not just the vocabulary but why nations choose one structure over another: independence for the states maximizes local control but sacrifices unity and effective national action.