The presumption against violence
Buddhist, Jain and yogic traditions give strong importance to non-killing or non-injury. The Ten Commandments prohibit murder, while Taoist compassion and Stoic justice oppose cruelty and uncontrolled aggression.
Defending another person
Strict nonviolence becomes difficult when an aggressor is attacking an innocent person. Refusing all intervention may leave the victim to foreseeable harm. The duty not to injure can therefore conflict with the duty to protect.
Necessity and proportionality
Defensive force requires a real threat, a protective purpose and no safer effective alternative. The force used should be limited to what is necessary. Revenge, humiliation and collective punishment are not defence.
War and uncertainty
Governments may exaggerate threats, conceal motives and underestimate civilian harm. Ethical evaluation must examine evidence, alternatives, probability of success, displacement, long-term instability and the treatment of prisoners and non-combatants.
Conclusion
Nonviolence should remain the starting presumption. Limited defensive force may sometimes be justified, but only under demanding conditions of necessity, discrimination, proportionality, accountability and serious effort to prevent escalation.