You have decided to try diplomacy. Although the United States formally recognized China in 1979, the relationship has never been a close one. U.S. support of democracy and arms sales to Taiwan has angered the PRC in the past, which sees such U.S. involvement as an attempt to foster Taiwanese independence. Conversely, the brutal crushing of student protesters at Tienamen Square in 1989 sent a clear message to America that the Chinese government has little regard for human rights. Based on past history, diplomacy may be difficult.
There are three diplomatic avenues you can pursue to resolve this crisis. In the first option, you can attempt to hold an East Asian Summit on the condition that China tones down military exercises, and apologizes for the downed aircraft. Second, you can attempt to hold talks with China and Taiwan immediately in Bejing. In the third option, you can expel Chinese diplomats from the United States, and sever all diplomatic relations.