The Cuban Missile Crisis was a domestic policy?

Technically, yes. A sovereign country can invite another sovereign country to host their missiles, especially if they have a powerful enemy nearby, ready to launch theirs.

> placing foreign nuclear missiles in your country to threaten another country

Clearly that's not "domestic".

Threaten another country? That's only one interpretation. I would say, to protect own soil.

lol - just noticed your stealth edit. I was quoting you.

First, let's not play whataboutism. Certainly the US isn't perfect. That doesn't make what Russia is doing ok. Second, Cuba is a totalitarian dictatorship. That's probably not the best example.