Whether they were abused children or oppressed people or somehow forced into a role they didn't want, does not alter what they are and how they behave. They must be dealt with as they are.
Pacifism is an opportunity for thugs.
Most bad people are cowards who prey on those who can not threaten them. They really don't care about moral right or wrong, or the appearance of courage or compassion. Threaten their well-being, they'll generally leave you alone. If you pose no threat, they'll tear you to pieces. That's why the U.S. needs a strong military and forceful foreign policy, and it's why individuals need the freedom to carry guns.