What was the main idea behind the Federalist Papers

Promote the US Constitution

Explanation:
The Federalist Papers were 85 essay published in 1788. They were anonymously published, but written by Alexander Hamilton (wrote 51) John Jay (wrote 29) and James Madison(wrote 5).

The United States was governed by the Articles of Confederation: an intentionally weak and decentralized body (they were afraid of giving the government too much power; they didn’t want a repeat of Britain). The creators hoped to perpetuate its existence, but it ultimately failed miserably.

Hamilton, Jay, and Madison recognized the faults and wrote the Federalist Papers to promote a new plan for government: The United States Constitution.