Phrase used as an add-on to sentences. "In America" fulfills the function of a prepositional phrase, though it is often used as a sentence fragment, and is used to convey an almost sarcastic outlook regarding the American mindset of independence and superiority, or a sincere outlook of such views, which is even scarier. This usage was started by LittleKuriboh's Yu-Gi-Oh the Abridged Series, which was first posted on youtube, but is now available other places as well.
This is the greatest movie ever. In America.
by Bandit Keith March 22, 2007