FILE - In this Sept. 14, 2014, file photo, Chinese tourists take souvenir photos with the Chinese national flag as they visit Quanfu Island, one of Paracel Islands of Sansha prefecture of southern China's Hainan province in the South China Sea. Vietnam's selection as the venue for the second summit between U.S. President Donald Trump and North Korean leader Kim Jong Un is largely a matter of convenience and security, but not without bigger stakes. Host Vietnam hopes to boost its international profile as diplomatic leverage against its big northern neighbor China, whose historical pushiness is manifested nowadays in its territorial claims in the South China Sea over waters claimed by Hanoi. (AP Photo/Peng Peng, File)