You don't understand. This is a beta (demo). They aren't showing you a lot of content because of that. The story will expound on some of the various NPCs, I'm sure. And what in the blazes are you talking about? The world is amazing, and filled with an incredible sense of detail. You must not have a background in game development, or you'd know that having the war end in a deciding factor pretty much requires them revamping the entire system for that area. The fact that a FPS has a random war like that occur in itself is an awesome feat. The fact you have an open world to explore is an awesome feat. If you want more interaction, go play Skyrim. But see, then you miss out on the dynamic world that Bungie has worked their asses off to create, that you dare call lifeless.