On the USS Stennis, pilots prepare for another mission over the Pacific. It's all part of Operation Valiant Shield, "a demonstration that America is present", explains Capt. Bradley. No one here will admit it but the deployment of 30 warships and several hundred combat aircraft is aimed at making China take note. It's the biggest show of American power in the Pacific for 30 years. Along with Operation Valiant Shield, Washington intends transforming the island of Guam into a 21st century fortress. "This is the largest transfer of forces in the history of the military", explains Capt Robert Lee. The base will cost an estimated $15 bn.