Two interesting things about the Japan tidal wave:
It occurred a mere 7 years after the Indonesian disaster. Never before has so little time elapsed between major tsunamis.
It was comprised of two separate waves, which stacked upon each other as they hit shore .. also a first in recorded history. This story was reported in Yahoo news, but pulled pretty quickly.
Coincidentally, I had read about Project Seal even before Japan .. a 1941 project taken over by US DoD in 1944.
Tsunami bomb - Wikipedia, the free encyclopedia