Those with a basis for comparison have certainly opined otherwise.
Certainly it has been one of the best, and could remain one of the best, ...but certainly is not THE best. 
Having actually lived for extended periods of time in countries all over the world, I have a basis for comparison. As usual, your lack of knowledge and thought show glaringly in your non-sensical posts.
Again, the United States is
The Best Country in the World.