Why did they not raise the USS Arizona?

Answer 1

During and after the surprise Japanese attack on Pearl Harbor in December 1941, many of the crew-members trapped in the (overturned) U.S.S. Arizona were not rescued because of the difficulty involved in cutting through the thick steel hull of the ship. It should also not be overlooked that rescue-efforts were initially delayed by the need to defend the Harbor against ongoing Japanese attacks.

Answer 2

It was too badly damaged. The forward magazine explosion destroyed the forward part of the hull, and then the forward deck collapsed down into the wreckage.