On Tuesday, an international tribunal soundly rejected Beijing's extensive claims in the South China Sea, an area where China has been building islands and increasing its military activity.
The case before the international tribunal in the Hague was brought by the Philippines, challenging what's widely seen as a territorial grab by Beijing. The tribunal essentially agreed. Beijing immediately said the decision was null and void and that it would ignore it. There are concerns now that the tribunal's decision could inflame tensions between the U.S. and China.