No, not saying it's good. I'm saying realists need to deal with the facts as they are, not as they wish the situation were. The Germans were expelled from the Sudetenland when Czechoslovakia was created. The Germans had settled in the Sudetenland and lived there for approximately a thousand years, but they were cleansed from the area after WWII, and they're not coming back. It's accepted that they aren't coming back to the Sudetenland, as unjust as it may appear. That's because it's impractical to change the facts on the ground, short of war.
If you choose war, prepare to suffer the consequences of loss. Germany lost a lot of territory after it lost the war. Had Hitler won, history would have told a different story, but he lost. That's fact, that's reality.
Israel exists today. Too many cry about what the area looked like under Ottoman rule (not Arab rule, Ottoman rule), but it would benefit them to look at the world today and see what can be done to benefit the Arabs that aspire to be Palestinians. Of course, they should not be surprised if they choose war, and lose, that they will lose more territory. That's why war isn't the answer, but since I'm not an Arab, I can't choose for them. They can fight, and lose more and more, as they have been losing more and more since 1948. Or they can try something new, and most likely gain.
Ethnic cleansing is evil. I don't believe ethnic cleansing is just, and it should not be employed. Ethnic cleansing is a monstrous act. But the so-called "resistance" and "intifada" is a form of total war, and total war can have ugly outcomes for the loser. If you don't know what total war is, please look into it. The reliance on pure guerrilla and irregular tactics could have (and has had) devastating consequences for the Arabs, and will continue to have such consequences as long as such tactics are employed. That said, I am not convinced that Israel will ever resort to ethnic cleaning, given that it has had that opportunity in almost every single decade since its creation, and never chosen that option.
Here's a counter-proposal: focus on building up the economy, and show the world, and indeed, Israel, that it can only benefit Israel to leave. Stationing troops, fighting wars, enforcing blockades--it's an expensive business, and a drain on the economy. Trade and peace contribute to economic growth. If I were Israeli, I know what I would choose. But I would only be able to choose trade and peace if such an option were available.