Yes, there are. I'm not familiar with the names and locations of the various museums there, but I do know that if you want to see Georges, Kates, Vals, and various other rare military artifacts, you should take the time to find out where they are. There's even a full-scale replica of the battleship Yamato - used in the filming of "Tora! Tora! Tora!" located in one of the bays (Tokyo Bay maybe?).
On the flight over, don't forget about the dangers of Deep Vein Thrombosis - blood clots that form in veins and soft tissue from staying in one position for too long. People have died from DVT clots moving through the blood stream and blocking a critical artery.