I'm just a layman on this subject, but it would seem that with how interconnected our world is, it'd be very hard for global warming to be a net positive for most countries. The topic of refugees alone has shown that destabilization in some parts of the world can have reverberations in completely others (e.g. Western Europe).

That said, the very rich who are insulated from practically any externality of climate change, many who are actively building doomsday bunkers, may look very keenly at the opportunities a societal upheaval may bring their way.