When wars are fought over territory, the losing side must vacate the contested territory. That is the way it works. You can be sure that, had the Arabs won in 1947, the Jews in Palestine would have all been deported or killed. There were thousands of Jews living in Kibbutzim in Jordan who were deported in 1948. Thousands of Jews whose ancestors had lived in Hebron for over three thousand years were ruthlessly deported by Jordan in 1920.
When you fight over land and lose, you LOSE THE LAND. Life is tough like that. They MUST LEAVE. That is the penalty for invading a country and losing.