Ender,
as apalling as genocide is, you cannot simply dispossess the people who have lived in an area for three thousand years to try to undo the harm:
Also, the six-year-old's argument "we were here first" isn't very useful.
FACT: the land is deeply contested.
The UN was trying create a compromise when it set up Isreal. But everyone needs to compromise to reach a peace, even the Israelis.
Come on now. What are we (humanity) trying to achieve here? Peace? Co-existence? Freedom to live life without fear of attack, and threatening no others? I hope so. Revenge is an empty vessel: it does not sate an appetite; it is the spiritual equivalent of drinking sea water.
Personally, I would have said that proper integration of the Jewish culture into the countries of the world, as has happened in the US (thankfully) is a much superior strategem than starting a turf war in one of the poorer regions of the world.
But there is an Israel, now. And there ought to be a Palestine, too.