It is a bit funny that you mentioned Canada - given that Quebec barely voted down independence by a 0.2% margin in 1995. Something that would have been a disaster for Canada to be literally split in THREE pieces.
..and it may very well have led to armed conflict as violence in separatist violence in Quebec was not uncommon.
Separatist movements are very very often superstitiously supported by foreign rivals and it is worth quite a bit of political power to physically keep you nation together.
> Individual states do not have the resources to oppose our military.
They do not need to. When independence movements are militarily squashed, that is when foreign rivals step in officially to fund and supply weapons to them. It happened in Kosovo, Taiwan, Donbass, South Ossentia, etc..
> I don’t think even hostile countries like China, Russia, Iran, or North Korea would even attempt to get involved in an internal conflict
I hesitate to even reply to this comment. I think you know, reading it, how wrong it is.