What does it mean to say the United States has a federal system of government?

A federal system of government is one that divides the powers of government between the national (federal) government and state and local governments. The Constitution of the United States established the federal system, also known as federalism. ... Only the federal government can declare war.

Explanation:

- three-quarters or two-thirds..

- "the constitution provides that an amendment may be proposed either by the congress with a two-thirds majority vote in both the house of representatives and the senate or by a constitutional convention called for by two-thirds of the state legislatures."

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an era of negotiation.

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