[Lisa]

I have an american bulldog, he's 10 months old, I have had hin for two weeks and generally he is very sweet, but he has become obsessed with terrorizing my cats, Does any one have any ideas how to stop this behavior.

Sounds like you have a normal AB. Were you not aware that AB's have a high prey drive prior to obtaining one? You should probably consider rehoming your cat before it ends up dead.