> Nothing should or would happen.

"nothing should" is correct; "nothing would" is fantasy

> The issue with Cuba was the stationing of nuclear missiles in Cuba, not merely its membership of a pact with the USSR.

Yes, putting nukes there brought things to a serious crisis, but the issue with Cuba

> The US didn’t invade Cuba, it assisted Cuban exiles to do so

Come on, let's be real here. Sure, _technically_ the US didn't invade Cuba. But it funded and assisted a mercenary force in a (very poor) attempt to do so. And that wasn't the only time the US tried to force regime change in Cuba, just like it did in Chile.