Why did the United States change its government from the Articles of Confederation in 1783 to the Constitutional government in 1789?

Choose one of the following topics below. Why did the United States change its government from the Articles of Confederation in 1783 to the Constitutional government in 1789? Include a thesis and historical details to back up your thesis.Compare/Contrast the relationship between the American colonies and Native Americans on the frontier during the Revolution War to the relationship between the United States and the Native Americans from 1789-1799. Include a thesis and historical details to back up your thesis.500 word