In all countries around the world, the duties of the soldier are codified in detail, but in very different ways, according to the various histories, and cultural backgrounds of the respective Nations. As this soldier has the right to legally use a powerful lethal force, a lot is required from him, which is normal. He is now most often a professional. He has mainly to master perfectly his weapons, to respect the Law of Armed Conflicts and to apply the principle of humanity. But his leaders have to guide him and his Nation to understand and support him.