Reply #5: define fail.

[some guy]

define failure.

If you want to think of the US as the world's longest-lasting democracy, we failed somewhere between "all Men are Created Equal" and signing the US Constitution, which set up a Republic, so that "all Men" would not have an equal say in how the nation was run.

If you want to think of the US as the world's best, and fairest, most generous and noble nation in history, we failed by 1803 when we paid France $15 million for land they didn't actually occupy, but gave nothing but pain, suffering and death to the people who actually occupied the land between the western edge of the United States and the Mississippi.

Has there been a generation since that time when the US has not acted as an empire?

I'm not sure what your question is, do you want to discuss when democracy failed, or when good Public Relations propaganda failed?