"Can the US withdraw from the UN now, finally?"
You mean like it did with the League Of Nations?
Cos that turned out really great for Hitler and Mussolini. Without America to provide a more strong arm in collective security Italy and Germany ran amok until the outbreak of WW2, cos Britain and France were in no military/economic position to stop them and the USSR was excluded as well.
"Can the US finally place the UN on the list of terrorist supporting organizations?"
You mean because they don't instantly demonize the other side? Because they actually listen to what countries like Iraq, Cuba, Afghanistan and Iran have to say for themselves?
"If Fidel Castro is so wonderful, and if Cuba is so wonderful, why doesn’t the UN move its headquarters to Havana?"
Duh, because they don't have a fancy building for it! Oh and Cuba is rather nice with better healthcare than the USA and Castro is a hell of a lot better than the USA puppet regimes that preceded him.
"Why don’t the Hollywood celebrities and Main Stream News Media sycophants who LOVE Fidel and his Cuba move there and live there?"
Well if you love Jesus so much why don't you move to Jerusalem or Bethlehem?
"Malicious, violent, sadistic thugs are in power and they are praised"
If you're talking about Castro, the choice for Cubans comes down to
1. Domination/exploitation by the USA and a puppet regime.
2. Castro, a righteous man who overthrew American control, brought them socialized healthcare and actually fought against the Bay of Pigs invasion of Cuba that the CIA set up to kill him. He may not be the messiah of leaders but he's not all bad.
"while good people and good nations are demonized and marginalized."
You mean like Obama?