A prima facie moral obligation is an obligation which has a strong moral reason supporting it. However such obligation may be overridden under special circumstances, like self-defense. Therefore it is ethically correct to harm someone else in order to protect yourself and others. The ‘just war tradition’ provides three fundamental moral reminders. The use of force is sometimes necessary to preserve values that would otherwise be lost. Any resort to force and the application to forceful means have to be subjected to an intentionality of justification and restraint, and the means and techniques of war should serve the legitimate moral aims of the employment force. Can war be ethically justifiable? Two sets of rules have been developed to assess when choosing violence can be justified, as well as to set limits on the amount of force. These two sets of rules are referred to as jus ad bellum, which is the right to war, and jus in Bello, which is the right in war. Jus ad bellum refers to whether the option to use force in a particular situation is justified, while jus in Bello refers to whether the type of force is to be justified. There are conditions in both jus ad bellum and in jus in Bello. The conditions in jus in Bello are proportionality of specific tactics and the immunity of non-combatants.