We have never been an imperial country, nor have we tried colonizing anywhere. I don't think it's a "tried and failed" it's a "Never tried."
Yeah we pretty much just support evil dictators that allow American corporations to do business in their country.
And we go over and blow up stuff and kill people to show them what nice folks we are so they will adopt the American Way of Life.
That's why the whole world loves the USA. But if these ISIS guys don't knock it off we might have to start getting rough