What factors during the colonial period caused the United States to become a democratic country instead of a feudal country in the future?

The United States was a British colony before Washington took over as president, when there were a large number of black slaves in the United States. When Washington took over as president, the United States got rid of British colonial rule and began to move towards democracy gradually, spending money to buy a lot of territory, but black slavery was still not lifted. Besides Washington, john adams is the second to succeed the President of the United States. His party is the Federalist Party, and it still pursues Washington's autocracy. The third president was Thomas Jefferson, who was a member of the Democratic Socialist Party, the predecessor of the Democratic Party. Since then, the United States has begun the road of democratization. During the civil war, all members of the Democratic Socialist Party were elected president. After the Civil War, the United States restored the freedom of black slaves, and blacks could become full citizens of the United States, but their identity was still discriminated against by white Americans.