In the application of the method of non-violence, one must believe in the possibility of every person, however depraved, being reformed under humane and skilled treatment.
The truth is that cowardice itself is violence of a subtle type and therefore dangerous and far more difficult to eradicate than the habit of physical violence.
Although under particular circumstances, the violence method - any method - can be justified, nevertheless once you commit violence, then counterviolence will be returned.