Not only cruel, but it constitutes animal abuse, and I cannot even imagine anyone's defending it if they truly love cats.  Thankfully, most vets will not perform the procedure except to avoid euthanasia by selfish humans.  Some veterinary schools do not even teach the procedure any more.  If people were to educate themselves as to what it is that constitutes declawing, they would NEVER subject someone they love to it.  Most people (I used to be one of them.) think it consists of simply removing the nail/claw.  This is not the case.  In order to remove the claw, the finger is pulled off from the last joint. Then the poor cat has to walk on those damaged hands.
(cont'd.)