If you were forced to leave your country and flee because someone took it by force. If it then took 300 years before your nation could muster the political influence to claim that territory back, would you, as one of those successors, do it? Or would you say "oh, it's been 300 years, well that was a long time ago, we might as well forget all about that". Would you do that? Because that's what the Jews are claiming happened at some point in the past. Are they lying?
Fact of the matter is, we now have laws against these sort of things, and countries have borders, respected sovereignty etc. The British promised to leave the region after the world war, but then instead they gave it to the Jews. Palestinians have a legal right to the land.
Alot of Berbers lived in Andalusia for a long time during the Ummayad rule of the region and were then forced out of it too. I guess since they don't have a separate independent country, why don't we just send them over to Seville to create a country for them there. Of course, that will have to be done with military force and we're going to have to force its current residents out of their homes and into refugee camps, we're going to need US and European backing too, but all that seems to be quite ok with you, so..
