They're setting up bases and stations all over Antarctica and need guaranteed access to build and resupply them. When the new protocol about using (not using) the resources in that area comes up for review again in 2048, China will have a say in how it can be used. THEY WANT the resources - coal, iron ores, manganese and hydrocarbon. China is taking the long view. China eyes Antarctica's resource bounty
Just curious but do we have a coast in Antarctica that needs guarded?