Subject: Why doesn't H-bomb cause the fusion of Hydrogen in ocean?

What prevents the hydrogen in the ocean from fusing (or negligible amount of 
fusion) during the event of an underwater hydrogen bomb explosion? Isn't the 
pressure and temperature produced by the bomb adequate to initiate fusion in 
the surrounding water's hydrogen? I'm asking only from curiousity, after 
reading about the conditions for fusion and the conditions created by a fusion 
bomb.

Re: Why doesn't H-bomb cause the fusion of Hydrogen in ocean?