China and the Pacific Island nation of Nauru signed a joint communique on the resumption of diplomatic relations. Nauru's move reduces the number of so-called "diplomatic allies" of the Taiwan region to only a dozen. And it's reported that Tuvalu, another Pacific Island nation, will review its relations with Taiwan after the national elections. Including Nauru, 10 countries have cut formal relations with Taiwan over the past 8 years. The U.S. however, expressed isappointment over Nauru's choice. Why is that?