Violence is stupid. In some situations, it's just an output for one's rage. In other situations, it's a battle of who is best equipped (hardware + intelligence). Neither of these address the core of the disagreement. Violence only beats the loser into submission. It does not change their stance on the matter.

Negotiation, on the other hand, ideally, at least gives all parties some gains and losses. It may not be the end of the matter but it's generally a positive step and should promote some degree of respect.

Maybe we never had it, but I think we've largely lost the ability to be respectful and empathetic to others. Even though we find to be of the greatest evil, I think, should be given some initial respect to try to understand the emotional reality of their intent.

I won't write it out, but imagine the worse crime an adult male could do to someone. Something so revolting that the only "logical" recourse is violence. This is an emotional response that does not address the problems that brought this person to such an evil act. By ignoring the problem and beating the person down, we are not able to understand how they got to this place or how we can recognize this path in others. This is a brief example for the sake of time. If you look at something like genocide, I think the process does scale up but too complex to write out for now.

I condone empathy for all because we all as a species benefit from it.

Edit: on second thought - violence used to preserve life may generally be acceptable.