RIMPAC the world’s largest naval drill in the Pacific region is underway. The biannual event started more than 30 years ago and has evolved into one that evolves many countries in the region, with 22 countries taking part this year. But China has not been invited this time, the only one of the five permanent members of the UN Security Council not to be. So far the US has not explained why. What is the significance of this year’s RIMPAC? Is it supposed to form an alliance? Is China being isolated as a result? What does it take to maintain peace and security in the Asia Pacific region? And what is necessary to avoid China and US to become major rivals in the region?