The power of water can be so destructive it can kill thousands of people in seconds with little warning.
The U.S. is lucky that it knew about a threat of a tsunami and had hours to prepare and evacuate following Friday's massive earthquake in Japan.
Japan was inundated with as much as 30 feet of water shortly after the 8.9-magnitude quake. Residents had about a 15-minute warning to get to higher ground. The death toll is already in the hundreds and still rising. Tsunami warnings were issued for the entire Pacific basin.
When a powerful earthquake moves the seafloor and displaces water, it spawns a tsunami, a series of waves that can travel through the water for thousands of miles at speeds up to 600 mph.
That's as fast as a jetliner.