Simply remind them that they would all now be slaves of the Third Reich were it not for the blood of many, many Americans.
Fifty years ago, before the bombs started dropping in London, many "civilized" Europeans (and some Americans, to their shame) were saying:
"You know, basically Hitler is right."
Whatever America's flaws may be, Europe's Marxist minds are virtually incapable of comprehending Freedom; therefore they hate its perilous implications.
They much prefer the peaceful, subsidized tranquility of a socialist welfare state, a state which is made possible due to the military might of the USA; through two World Wars, they have been either unable or unwilling to defend themselves. Just remind them of that and they should pipe down. And remind them that socialist governments killed more people in the 20th century than all other causes combined.
Winston Churchill was the last of his kind in England, I fear. All that is left now are socialist appeasers who wish to propagandize their people into the EU nanny state.
OK, I'm done ranting about Eurosocialist ingrates whose asses we saved twice, for now...
You didn't save anyone's ass, Sargon.So don't try to attach yourself to the coattails of the American servicemen who fought in Europe.
The only thing you have in common with them is your country of birth.