After previously committing to stop building up its military presence in the Spratly Islands, an US think tank has analyzed satellite images of a Chinese installation in the South China Sea and determined the Chinese have put in anti-aircraft guns on at least one of their artificial islands. Often a forgotten-about issue with everything else going on in the world today, the Spratly Islands are hotly contested. China, Vietnam, the Philippines, Malaysia, Taiwan, and Brunei are among the countries that claim territory in the island chain.

While previous administrations have timidly/bravely sent a ship or two through some shipping lanes in the region, you can bet that the President-elect will be watching this build-up closely. After challenging the One China policy publicly last week, Donald Trump has proven that he’s not backing down from China. And while I believe his flub last week was more ignorance than planned execution, he is in a position to confront China on its refusal to conform to the findings of an international tribunal in July 2016.

Per the BBC:

In a report on Wednesday, the Asia Maritime Transparency Initiative (AMTI) said it had been tracking construction of hexagon-shaped buildings on four of the Spratly islands for several months. It said the new buildings were an “evolution” of structures on the three other islands, but it was now confident that all of the buildings housed military defences.

The group says that some buildings “host what are most likely anti-aircraft guns” which have visible gun barrels in satellite images, while others are probably what it terms close-in weapons systems (CIWS).

CIWS are defence platforms used to detect and shoot down missiles and other aircraft.

Some of the structures have been buried, the group said – which would make them less vulnerable to enemy strikes.

“These gun and probable CIWS emplacements show that Beijing is serious about defence of its artificial islands in case of an armed contingency in the South China Sea,” AMTI said.

“Among other things, they would be the last line of defence against cruise missiles launched by the United States or others against these soon-to-be-operational air bases,” it added, in a reference to previous photos which seemed to show aircraft hangars being built.

China’s Defence Ministry said on Thursday that its deployment of military equipment was “legitimate and lawful.” A brief post on the Defence Ministry’s microblog site described the equipment as necessary and defensive.”

Image courtesy AMTI