US and Japanese warships in joint exercises
13 December 2010 Last updated at 07:17 GMT
Warships from America and Japan have just completed their biggest ever joint exercises, as tensions remain high in East Asia.
They follow recent war games between South Korea and other Asian nations which were designed to show the military strength of America and its allies.
The BBC's Asia Correspondent Alastair Leithead joined the American aircraft carrier, the USS George Washington, off the coast of Okinawa in southern Japan, and sent this report.