The regular incidence of war going on on our globe suggests that's not sustainable. Why do you think countries spend so much money on their militaries? Me, I'd love it if we could zero out the US defense budget. Unfortunately, that would be a disaster for us.
Who controls what territory in the world is hardly stable. At some point, if one is not a military power, one will have to take sides. If, for example, valuable resources are discovered in Greenland.
What are you talking about? Greenland is already a NATO member (via Denmark), so it has already taken a side. The obvious scandal, of course, is that Greenland is being openly threatened by the US - a fellow NATO member!