ABOARD THE USCGC WAESCHE — China has been boarding ships looking for mock pirates and contraband as it joins the world's largest maritime exercises for the first time.On Wednesday, Chinese sailors from the destroyer Haikou boarded the Coast Guard cutter Waesche for a drill checking cargo as part of Rim of the Pacific exercises the U.S. is hosting in Hawaii waters this month. The Americans played the role of a merchant ship carrying valuable paintings.Coast Guard Lt. Gregory Ostrov, exercise safety officer for the drill, said the Chinese sailors were eager to cooperate and demonstrate their proficiency as mariners."It was a lot fun. It was a great opportunity to build interoperability and also share tactics and procedures and just observe the way they conduct the same missions as we do," Ostrov said.China will also participate in a humanitarian assistance and disaster relief exercise. The hospital ship Peace Ark is among the four Chinese ships in Hawaii. China has four ships and two helicopters at the exercises.Nicole Forrester, a former Australian diplomat and senior international relations adviser at Pacific Forum, a Honolulu-based think tank, said the exercises allow nations to understand one another better. This is critical, she said, to maintain the peace and security in the Asia-Pacific region."Misunderstandings lead to miscalculations, and miscalculations lead to escalations and escalations can lead to conflict," she said.Denny Roy, East-West Center senior fellow, said miscalculations are a real concern as the Chinese navy grows and becomes more active at sea."There's a greater chance than ever U.S. ships and aircraft and Chinese ships and aircraft might bump into each other in the Asia-Pacific," Roy said.The immediate problem is developing protocol for navies to follow to prevent the accidental escalation of conflict, Roy said. In the longer-term, understanding one another's strategic view of the world may help each side feel less threatened.Nearly 50 ships, 200 aircraft and 25,000 military personnel from 22 nations are in Hawaii for the exercise. The drills began in late June and last through Aug. 1.