If you keep people hungry and in fear, they will (with exception of those who really want/accept to be martyred) do everything to escape..... for me all that is currently happening matches with such a strategy/scenario... and although 2 million people on the move seems unimaginable, we are in the end a flock of sheep. If Palestinians become a diaspora this way (West Bank being next towards Jordan?) and spread over multiple countries, they will unlikely be able to send rockets to Israel any longer... and if they lose their UN right to return and become citizens of their host countries over time, the Hamas movement will likely fade away. However, you are fully right, if people stay near, you will need serious peacebuilding because in the current situation there are enormous levels of hatred seeded and therefore Israel will harvest combatants/ terrorists.... on their other side.....