Welcome to Eagleland, bitches! We're rich, industrious, militarily powerful and burningly patriotic! How to show that in fiction? Why with Giant Robots of course. An American Robot, in short, is any super fighting machine that hams up the USA to the power of eleven. Expect them to be decked out in the stars and stripes and packing the heavy artillery (as well as having a burning American pride).
Examples [tvtropes.org]