The recent events in Japan have sparked more interest in the idea of survivalism. Although earthquakes are not as frequent or sever here in the States, they are a possibility. We all should have have some food reserves on hand along with knowledge of the area so that when disaster strikes we can be ready. The east coast has huricanes to deal with and the west coast has earthquakes and tsunamis. However for the most part, many of the tsunamis have not been too bad. Most of the damage in California was a result of people who left their boats at the dock instead of taking them out to sea.
Tsunamis out at sea away from the continental shelf are nothing but another wave for a boat on the surface. The real power is underwater where the force "rolls" along the bottom rising with the slope of land. Tsunami power and destruction happens when the water lifts up following the land until it runs out of ocean area and hammers what is normally dry land.
The reality check here is that no one can be prepared for any and all situations but at least we can prepare for the most common possible ones. If you live within a 100mile distance from a nuclear facility you should prepare for worst case scenario that could happen with the facility. Japan has had some scares with low levels of radiation and partial meltdowns. Those people living near nuclear facilities should consider escape routes if time permits and facility integrity is compromised.
If you live near a large body of water such as an ocean then hurricanes and tsunamis are a concern. Think about geologic activity, California has to deal with that. The USGS has information you can look at to determine if earthquakes are happening in your area. Some have low intensity so they may not be felt by the humans living in the area in which they occur.
The knowledge to gain from current news events is simple. We all must understand our limitations, improve our weak areas, and smartly store water and food for times when they will be hard to aquire. Most events will be short term that we live through, maybe lasting only a few months at the most. Any longer than that means the area or house you were living in was destroyed along with your thousands of dollars of gear and food. Don't go crazy trying to store tons of goods. If the time comes, you may have to ration what you have but at least you'll have some food to eat when many others are starving and dieing. Remember the rule, its good to give but you will be compromised and your stores taken when civility are replaced with hunger and greed.