The Europeans didn't think it was a bluff.

But more generally, when the foundation of your country's morality is "all men are created equal" you really have given up the space to object to others doing what you do.

If honour is a thing.

I don't think Trump is bluffing. However Americans in general are opposed to taking Greenland, and so if Trump does anything I expect Americans/Congress to raise up. Europe should be concerned because this will take months to play out.

Nobody said bluff but you, and honour is long gone.

That just leaves the facts. Which do you think is more credible and likely?