Yes, China threatens Japanese islands in the East China Sea and all the way up to Okinawa, in theory. So Japan has to take the lead in defending their territory:
Tokyo and Washington must debunk such thinking. By hardening the Ryukyus against seaborne and airborne assault, they can drive up the costs of an island-hopping expedition to prohibitive levels. Advance precautions can make the islands look unappetizing indeed. And a cautious China is in everyone's interest.
But drawing a line well short of the Senkakus risks a war outside the defensive perimeter the author suggests. If Japan and America resolve to harden the Ryukyus, don't we just tell China that they get a free shot at everything south and west of that hardened perimeter?
By all means, harden the Ryukyus. But that's not enough.
I don't suggest sending troops to those exposed islands south of that perimeter. But Japan can and should send in the robots to defend the more exposed and tiny islands:
It strikes me that Japan could defend their claims to the Senkaku islands by using CROWS and unmanned radar on the islands themselves supported by armed UAVs patrolling the area.
China would at least have to fight to take the islands--assuming Japan is willing to pull the trigger against perhaps unarmed Chinese sent ashore in a first wave to disable the robots (well, remote weapons stations, actually) ashore, thus requiring China to escalate to military forces.
If the Japanese have the capability to rapidly deliver sea mines by air if a Chinese move is detected, more robots could be put in place to keep the Chinese away from the islands in the first place.
It may be that the robots could focus on disabling any Chinese ships nearby while not shooting at unarmed Chinese "fisherman" who come ashore. Then the Japanese could send their coast guard to evict the unarmed occupiers.
Or perhaps some of those CROWS could be armed with water cannons rather than machine guns.
If China does fight to gain the islands, Japanese military assets in the hardened area could then move to defeat or isolate Chinese forces in and around the more distant islands that China takes.
Fighting for land is supposed to be so 19th century. Or was it 20th century thinking? But when the disputes are over land, sometimes you have to fight for the land.
