Thread:UndeadHero/@comment-5870856-20141015025126/@comment-5135903-20141015152653

I think that America's decline as a superpower is more likely to happen in the early, rather than late, 21st century, as reports by the US National Intelligence Council are stating that, by 2030, the US will no longer be the dominant power in the world.

You're right with the idea that declining superpowers become more imperialistic ('flexing their muscles' and such), but in the end it usually ends badly for the superpower.

If you really wanted an excuse to invade Canada, you could invoke climate change and aquifer depletion, which are leading some to predict the end of farming in the US west of the Mississippi. The US would have to rely on the Old Northwest for its food by pumping water from the Great Lakes; because the Great Lakes are joint-owned between Canada and the US, Canada would probably want concessions.

Though it may be a bit extreme, the US may try to take the Great Lakes by force through invasion of Quebec and Ontario. The problem with this is that it's likely that Europe would probably be importing a lot of food from Canada (because they definitely wouldn't want to rely on Russia, the other likely major food producer under climate change), so an American invasion of Canada, especially its Atlantic coast, would be a threat to European food security.

This is the problem with the 'America invades Canada due to climate change' idea; an invasion under such circumstances could end up bringing the whole of the EU down on the US. With many Chinese farmers already beginning to travel over to eastern Russia to leapfrog the expansion of the Gobi desert (something that is happening now; some even think that it may lead to changing borders in the future), everyting could kick off at once, leading to some sort of World War, with the EU and Canada vs. the US in the west and Russia vs. China in the east!

Come to think of it, having some sort of North Atlantic Coalition between Canada and Europe as a superpower might be quite original.