The right of the United States national government to establish post offices, regulate commerce with foreign nations, and declare war, all on behalf of the constituent states are referred to as

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The right of the United States national government to establish post offices, regulate commerce with foreign nations, and declare war, all on behalf of the constituent states are referred to as enumerated powers.

These enumerated powers can be found in the Constitution of the United States, created during the Constitutional Convention held in Philadelphia, Pennsylvania in the summer of 1787.

During this convention, delegates met to discuss and create a new form of government for the United States. Federalists like Jhon Jay and Alexander Hamilton debated with Antifederalists like Thomas Jefferson and Samuel Adams. The Constitution was finally signed by the states of the Union when Federalist James Madison drafted the Bill of Rights that is the first ten amendments to the United States Constitution.

using the scientific method.