I have found all cat owners to have the same ignorant attitude.
He knows that I will kill his cats if I manage to get my hands on one
whilst it is crapping on my property.

Isn't this getting a bit stupid? I can tell you if anyone killed my cat
they would regret it because he is a beautiful soul. and if you killed him
I'd pursue you to the end of the earth to make sure you went to prison if
you did.
Or if I found you first.
I am fairly kind normally, but best not to threaten my cat.