Ahem, why has the US gotten involved in political and social issues across the globe for the last several decades?
If the US was truly isolationist then you might have a point but... err... it isn't. The US has global influence. The US - and US citizens - LOVE to crow about how much global influence they have. Global influence comes hand in hand with global interest. Give up your influence and become a truly self-sufficient isolationist state or calm down and deal with the fact that internal US politics DOES affect and IS relevant to the rest of the world.
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