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!
Well, US has the base near Guantanamo; I haven't been to that side but I have been to Guantanamo proper... trust me, that place is hot and has mosquitoes and two decades ago the naval base was almost as infamous as North Korea. And then there's the newly opened "alligator Alcatraz"... I think Mr. President have gotten some ideas for Greenland :-)