Final answer:
California has experienced fatalities from tsunamis in the past, such as the 1964 Alaska earthquake tsunami that impacted the California coast. Tsunamis are often caused by seismic events, including earthquakes near or under the ocean, and California's seismic activity is linked to the San Andreas Fault.
Step-by-step explanation:
Contrary to the claim mentioned in the question, California has indeed experienced fatalities from tsunamis in the past. Earthquakes, especially those occurring near or under the ocean, can be potent triggers for tsunamis. These seismic sea waves are capable of causing extensive damage and loss of life upon reaching coastal areas. An example is the 1964 Alaska earthquake, which generated a tsunami that affected the California coast, resulting in fatalities and significant damage in places such as Crescent City.
Furthermore, historical records and geological investigations suggest that tsunamis have impacted California's coast multiple times in the past, whether initiated by distant or local seismic events. However, it is true that the deadliest earthquakes and tsunamis, such as the 2004 Sumatra event and the 2011 Tohoku earthquake and tsunami in Japan, have occurred along subduction zones - regions where one tectonic plate is being forced under another. California's seismic activity is largely a result of the San Andreas Fault, which is a transform boundary where two plates slide past each other, rather than a subduction zone.