Please help clarify why he has a bad attitude?

My cat is mean! He does not like to be touched most of the time. He will approach you lovingly, and suddenly pounce on you and bite. We cannot allow him to be around little children because we fear he will try to hurt them. At other times, he will just jump up on you and begin cuddling, but you cannot touch him or he will get mad and bite. He was abandoned as a kitten and we took him in. Do you think this could have something to do with it? He has been neutered and declawed as well. He is not the only cat in the household, and tends to bully the other. He is a male - could this be a dominant male attitude? Please help... what type of therapy should he get if any?