The war was over, but the new nation and its states still had work to do.
In 1787, Hamilton and 54 men from different states arrived in Philadelphia, Pennsylvania. They talked and argued for four months about how our country should work. They finally finished a document called the U.S. Constitution. It described a plan for our national government.
All of the states had to approve the plan. But there was a lot of disagreement. It seemed doomed to fail.
Hamilton refused to let that happen. He helped to write the Federalist Papers, essays praising the Constitution. Once again, his words worked. The states approved the Constitution. It became the law of the land in 1788.