Iwakuni is home to U.S. Marines as well as Japan Maritime Self Defense Force (JMSDF).
When I visited the show I was only able to see JASDF/JMSDF aircraft in flight, but the recent show do have USMC aircraft demos, too.
The static display has massive number of aircraft and is worth seeing.

If you are interested in visiting this airshow or any other Japanese Airshow featured in this site, please refer to the page "Guide to Visiting Airshows in Japan"

US-1 flying boat (9082) of JMSDF 71 Flight Sqn stationed in Iwakuni.