Secretary of State John Kerry arrived in China for talks late Tuesday after spending two days in meetings with Southeast Asian nations to urge unity in the face of Beijing’s increasingly assertive behavior in the South China Sea. As WSJ's Felicia Schwartz reports:

China’s territorial claims in the disputed waters, including the construction of artificial islands and airstrips, will be a major topic of discussion on Wednesday and have become an irritant in the bilateral relationship as the U.S. seeks China’s cooperation on other issues. One of those is also at the top of Mr. Kerry’s agenda here Wednesday: pressing China...