Self-defense sometimes does require violence, of course. If ISIS, antifa, blm, or any other person/group is intending to harm someone and/or their loved ones, we are permitted to protect ourselves and fight back. It's the glorification of vengeance and reckless retaliation that is unbiblical and misleading.

When they came to arrest Jesus, Peter fought back and cut off someone's ear. Christ rebuked him for this. It wasn't for the act of self-defense, rather for Peter's unwise decision. God's plan was for Christ to die on the cross for our salvation, and Peter's actions stood in the way of that. We must discern, with God's help, when is the right time and the right way to act.