If my parents had said to me when I was a kid that Japan is the only country where we belong, that the Japanese people are the only people that we are related to, I would have to respond by saying:
wait a minute now, none of what you are saying makes sense to me because we do not even speak the Japanese language, we do not even know how to cook Japanese food, we do not know how to write with the Japanese alphabet, we look completely different from the Japanese people, there was never a time that I can remember that any Japanese people had come to visit us, we have never visited Japan, we do not have any Japanese friends or acquaintances. So what exactly could the connection be? The Japanese to us are like any other foreign people out there in the world.
And that is exactly how the European Jews should respond when anybody is telling them that only Palestine is their country and no other place.