Well Mike, to answer your question in the simple terms: yes, there are signs all over.
now, more in depth....
the hard part can be finding some of them as the cities here basically built around any of them. Most of them where cleaned up though. The Okinawans do not consider themselves Japanese... and they dont like being called Japanese either.
On Kadena AB there are a lot of WWII Jap buildings... well, not a lot per say, but many.
there is a cave by the golf course that is said to be haunted, it is a location where I believe 20 or so Japanese nurses commit suicide at a field hospital because they did not want to be captured, and it is said that cave is haunted.
Also the underground Naval HQ is in Naha, and is a popular tourist spot for Americans, and a regular history field trip for Okinawan student... it is interesting to see, I cant imagine what it would be like to operate in such a small area.
there are sheltures in the side of the hills on base that look like fighter sheltures, but the seem to small to me... probably because I am used to the larger ones of today.
There is so much history around this place it is un believeable.. there are shrines and burial sites for people from centuries ago. But you could hardly imagine what it must have looked like in the 40s due to the cleanup that was done, as well as the cities all around.
oh yeah, and they did just pull a Jap tank out of the ground in Manila. The old timers there said that they have been trying to get the local govt to dig it out for years. American tanks pushed the tank into a ditch to clear the road, and the ditch turned into just the side of the road after many years... cool huh?
A man's country is not a certain area of land, of mountains, rivers, and woods, but it is a principle; and patriotism is loyalty to that principle. ~George William Curtis