This isn't really such a shock, is it? I would imagine the US had pretty much the same types of plans in place.
Yup. They were called nukes.
I don't doubt it one bit. I wouldn't be suprised if we have contingency plans to overrun Canada. After all plans like this are written up all the time. It's where liberals get their "Bush planned this" and "Bush planned that" complaints.
Ive heard it said that the Brits were more prepared for a war against us than the nazis going into WWII. All sensible nations make their plans ahead of time rather than later.