The necessary consequence of man’s right to life is his right to self-defense.
In a civilized society, force may be used only in retaliation and only against
those who initiate its use. All the reasons which make the initiation of
physical force an evil, make the retaliatory use of physical force a moral
imperative.
If some “pacifist” society renounced the retaliatory use of force, it would be
left helplessly at the mercy of the first thug who decided to be immoral. Such
a society would achieve the opposite of its intention: instead of abolishing
evil, it would encourage and reward it.