For what it's worth, I don't see any country invading the US any time soon.
First, we've got the strongest military in the entire world with the most aircrafts and sophisticated weapons.
Second, if there is anything that unites this nation above all things, it's war. Americans (the vast majority) are super patriotic. Even the tree huggers that hate the idea of war, do want our troops to win and come back home safely.
Anyone tries that shit and it will lead to World War 3 and the US erasing countries with nukes.
I can see a financial collapse as more viable, but not an all out war and invasion.
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