Originally posted by ~Wålshy~
if it was underwater wouldn't it like move the sea bed and then like mess up stuff i dunno but where underwater was that if you know
It was only tethered underneath an amphibious assault ship, not right on the bottom of the sea. It was exploded in the Bikini Lagoon, in the center of the Bikini Atoll. It completely vaporized the ship it was tethered under, and caused significant damage to other target ships, along with contaminating pretty much the whole lagoon with radiation. This explosion was the reason that residents of the Bikini Atoll had to be evacuated, since they got their food from the lagoon, which suddenly became radioactive.
Here's a fairly low-quality video of Crossroads Baker:
http://www.youtube.com/watch?v=maLFSw-wtZA
By the way, how do you embed a Youtube video in your post like you did, Mr. 3l?