In 1776 America delcared independence and fought a war against their colonial masters to get it. With the help of France and Spain they achieved it.
They had a high quality of life, a booming population, a gigantic country and possibly the most raw material in the world. They were the only true democracy in the world. As we all know, after Thomas Jefferson bought Louisiana(An area larger then France, Spain and Germany combined) things went south do their repartions to Britain, defeat by Mexico, Indian guerilla attacks that still go on to this day and their successionist movement.
Your challenge is to turn America into a prosperous nation. At least a second tier great power(Think Italy, not Britain or France) which is NOT impossible. Bonus points if they expand to the West coast or are a Super Power.
You had a POD of 1783.