Where can I find out about the founding fathers of America and America's political stances, etc?

I was thinking about past powers on earth Rome, UK, etc seem to all be the major power due to military action, but America seems to be just good off what I want to know. Why has America been constantly progressive, is it something to do with the constitution, the idealogical stances of the people in America.
Where can I learn about this and Americas history to give me an insight to why America has been so progressive from it’s start almost.