In an ideal world, there would be nothing to protect ourselves against. No violence or slander, no vandalism or sabotage would exist. In this ideal world, there would be no war and thus, no need for soldiers to fight those wars. Unfortunately, we do not live in an ideal world. In this world, every light must also cast a shadow and every war needs warriors.
Thankfully our ancestors have left us with the hidden knowledge of both the natural world and the world of spirit that we may become spiritual warriors.