notalone,
It depends upon how you consider someones thinking and beliefs as being 'violent'. You say that JW's believe that people will be destroyed at Armageddon, and hence they are violent. With this logic, even Jesus Christ was a violent person, because he too told about everlasting destruction upon people; as in, in his parables, he told about people on his left going in to everlasting destruction (Matt. 24:45,46). Paul told in 2 Thess 1:7,8 that Jesus would come with his angels and will bring destruction on those who do not listen to his good news. So yes, Jesus was a violent person too.
If hating someone is a sign of being a violent person then yes, Jesus would be classified as violent too, because he openly rebuked and cursed the Pharisees. Jews were violent too because they openly asked Pilate to execute him.
If simply wishing harm on someone means being violent, then many of us would be classified as being violent for we wish that ISIS is wiped off from this earth.