China is building islands in the South China sea and its causing disputes among the other nations in the region; Malaysia, the Philippines, Brunei, Vietnam, and Indonesia.
image credit: nytimes.com
The US has many allies in the region and uses its massive Navy to patrol international waters, keeping shipping lanes open for trade
China has been rapidly piling sand onto reefs in the South China Sea, creating seven new islets in the region. It is straining geopolitical tensions that were already taut.
It’s also possible that building the “islands” is an end unto itself. Under the U.N. Convention on the Law of the Sea, submerged features (such as shoals) cannot be claimed by any party.