How would Catholics feel if the Vatican was destroyed?
They would not set out to murder everyone involved. Depending on how it were destroyed they would seek redress through the courts if possible, or if because of a War, Italy's allies would seek redress through military action.
Just like when people make fun of God, Jesus or any Christian artifact or personage, Christians do not riot and destroy buildings and murder people for it. Now go say something bad about Mohammad and see what happens if Muslims know about it.
Hell people died because of Cartoons.