I wonder why Tolstoy doesn’t give us Pierre’s argument about war. Perhaps he’s saving it for later?
Pierre sees the friendship between himself and Andrei as extending outwards, so it all seems to happen naturally and without effort that everybody at Bald Hills likes him. We could contrast this with his apparently unsuccessful attempts to help the serfs on his estates — where his kindness is intercepted and perverted by the managers. I could extrapolate this to a recipe for ending war:
(a) remove the vested interests connected with military activity. And
(b) teach people to expand their sense of “friend” until it includes the whole of humanity, and there are no more “foes”…
(so that’s easily solved)