Those who believe bad guys "out there" justify "borders" and cops here remind me of the puppeticians of Chicago and DC who blame their staggering murder rates on the freer regions (those with slightly less horrible anti-gun "laws") surrounding them.
There will always be somewhere else that you'll see as a threat when your carefully crafted scheme fails to deliver what you promised. Because governing is a lie, you will always fail.
Unless you have a "one world government", someone will be outside your (always illegitimate) jurisdiction and will have influence in your domain.
The solution isn't to more fully dominate and molest the people near you- it is to step away and stop governing and let people solve real problems (which are much more rare than the statist's imaginary ones) themselves.
Politicians are just bullies who create problems, then promise- and fail- to solve the problems they created.
Liberty works while bullies twerk.
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