that's understandable and all, but i think we can represent a global coming together without having all the pieces focus on war & peace. that's all. i think by picking such a polarizing focus, you'd not only be leaving behind a lot of good poets/poetry, but also a chunk of readership.
to go along with my post above, i think that as long as (whatever it ends up being) is put together nicely and the content is excellent, we won't need to rely on a slick cover or title (or a sweet smelling page) to make this book go over well.
so i think that you could incorporate those themes into a larger "global postcard", but i think it would be a shame to narrow the focus down too much.