The link is to studies of the Japan tsunami. It is worth watching the video.
My one thought is that the next tsunami from a subduction quake in the same area might have the highest waves in different locations. Also, that maybe parts of this area get a subduction quake and deadly tsunami every 100 years but that one as big as this one, the M9, might only come to that particular coast every 1000 years (for example, 869 then 2011). But, sure, build defenses, but as the video and story suggest, use what is learned elsewhere; for example, southern Honshu and Kyushu. I'm not familiar with the northern California through Washington coast, and I don't know whether a tsunami could come way up the relatively narrow Puget Sounds to Seattle (or up up the Columbia River...)
Chris

• tsunami study