You have mentioned this previously in Canadian threads, a scenario where America abandons the defense of Canadian territory during a high-intensity conflict with China and Russia. I still maintain that the US will militarily defend Canadian territory the same it would defend Washington State or Idaho or Minnesota etc.
Maybe. Depends on definition.
If the US has to choose though, between Guam and Northern Canada? Which priority will it give? Where is it going to put resources? Where are those resources operating out of. What is the threat each is facing, why are they facing the threat? Which is going to be delt with first, which is most urgent?
Guam is under a different threat from Minnesota. Guam has a strategic position, is a major military base and overseas territory. Is the US realistically going to divert resources from Guam, fail to protect its air and naval bases, its ships, and planes, 220,000 Americans, to protect Canada's North west passage?
I think the problem, the disconnect, is that Canada and the Canadian point of view doesn't really have a vignette that is realistic or applied to its current situation. I don't think there has been a lot of thought about situations where such things may arise.
Perhaps they just are too unrealistic.
Another consideration is the cost. Sure the Americans come, but at what cost. Because they won't be on Canada's terms.
Another is which America, and what sort of Americans? Recent events in the US have showed, you may get a presence, but it may not even be conventional military, it could be a Federally controlled paramilitary group. ICE in Vancouver, to protect military equipment and bases.
The honest reality is that for military purposes, Canada is a protectorate of the United States. Especially with the current US administration, we wouldn't probably even have a say how the US would deploy it's military resources in our territory during such a conflict.
Even Americans would probably advise you that it isn't a good thing. In great power politics, you want some leverage, even with
friends. But particular with large powerful belligerent friends, fighting and existential conflict both externally and internally.
Even during an internal crisis or civil conflict in the US which you allude to, Canada would likely have to pick a side and our fate would be intertwined (unlikely the British Empire will keep US civil war 2.0 south of the 49th parallel).
So Canada as a target of early neutralisation? You guys have oil right? Venezuela 2.0
Maybe its just how my kin see the world, but I do not see a world where Canada needs a weaker, less capable, more dependant military. I do not see how Canada can look at current events and think, there are no concerns, that existing thinking and strategies will be successful.
I think the US suspending Permanent Joint Board on Defense, is a clear signal of that.
Future moves could include disbanding it and taking required sites off Canada.
Any war in our neighbourhood involving China or Russia will be likely be via missiles (probably mostly ballistic). WTF would the US roll troops and weapons to in Canada and what would be the advantage over the lower 48 states? Russia has no ability to invade over the pole or through Alaska. China has better options via its navy and massive industrial capacity and naval launched drones and missiles would be their first strike options.
I think this scenario is dated. That may no longer be true within 10 years. Drone and robots are coming. If China lands 1 million robots and drones in the North west, and they start moving south, simply to create problems closer to home for the US, what do you think the US reaction will be? Bearing in mind that the whole reason they are attacking is so to cause the US to redeploy its forces to fight them, resources it has limited amounts of. I don't think 1960's scenarios of just ballistic ICBM carrying nukes is the only scenarios in play any more.
What if China forces the Northwest passage issue. They do exactly what the US is doing around Taiwan/China, but they do it in the northwest. They sail ~30 submarines, a couple of carrier groups through the northwest passage in summer, a particularly hot summer in 2030. They do it because they claim its international waters. They move their fishing fleet into the area. They are backed by J20s and bombers operating overhead.
China is not the same actor as soviet Russia. In some ways it less straight up combative. The Chinese tend not to be as reckless as the Russians. But they are far better equipped, far larger force, way greater technological capabilities. They aren't really interested in destroying the west, as they are in controlling it and running it. The Chinese never really subscribed heavily into MAD escalations.
The Chinese don't have to threaten nuclear weapons. They have conventional capabilities that can rival the US. Something the soviets never really had, certainly not in a expeditionary way.