The media watchdog STATS takes a good hard look at the reality behind the hype surrounding the supposed threat to Europe and the East Coast from the collapse of part of one of the Canary Islands. This formed one of the threats referred to in the article Jonathan Adler commented on below.

As STATS found, referencing one of the world's leading tsunami experts, fears of Deep Impact-style tidal waves are irresponsible exaggerations:

Specifically, the shorter period and wave amplitudes in his model, result in significant wave height attenuation with distance - to less than one-third of the shallow water amplitudes. The upper limit of his modeling study shows that the East Coast of the U.S. and the Caribbean would receive waves less than 3 meters high. The European and African coasts would have waves less than 10 meters high. However, full Navier-Stokes modeling of the same La Palma failure, brings the maximum expected tsunami wave amplitude off the U.S. east coast to about one meter.

[Emphasis added.] If this is the measure of the threat, a good pair of Wellington boots would protect even beachfront property.