There's a debate raging (ok maybe not raging) on DovBear's blog about Halacha (Jewish law) and transfer. For the politically uninformed transfer is a euphemism for removing the Arab population from Israel and the West Bank; in other words, ethnic cleansing.
What exactly does Halacha mandate regarding transfer? Well, to start transfer is a state issue, not an individual question. What's the difference? Let's say Halacha prohibits the permanent sale of land in Israel to non-Jews. This Halacha will apply in two different situations. First, any individual who follows Halacha would be obligated to discriminate against non-Jews and not sell him the land. That much is probably clear.
However, should the State of Israel pass a law outlawing such sales? That's a different question and one I would answer in the negative. It's the same by Shabbos (Sabbath). Every individual Jew must follow the laws of Shabbos. But I do not believe the government should mandate Shabbos observance.
Transfer is a public question. Expelling every non-Jew who denies our right to the land (and doesn't follow the sheva mitzvos b'nei Noach/Noachide code) is a policy only the state can carry out. So the age old question of whether the government should apply Halacha is relevant here. I believe it shouldn't because forcing Halacha on an unwilling populace is counterproductive and would decrease observance.
Besides for the question of whether the public policy of the State of Israel should be guided by Halacha, there's also an issue of the relevance of the question in the first place. Halacha, like all systems of law, apply legal norms to fact situations. The applier is someone fluent in law and with good judgment and a proper understanding of the factual circumstances. If the applier is missing the facts, he cannot give a decision, because the facts are integral.
The transfer question is, as legal terminology would put it, not ripe. The State of Israel is not going to take upon itself the strictures of Halacha any time soon. So all we have right now all hypothetical predications about the ramifications of transfer. These ramifications are facts relevant to the decisions. So any legal decisor who issues a ruling without these facts is giving an incomplete decision and one that isn't binding.
A supporter of transfer might argue that the Halacha has already been decided because the Rishonim (early legal scholars whose opinions carry great weight) are unanimous. I don't think that's true, but that's not relevant anyway. The Rambam (Maimonides) lived over a thousand years ago. His opinion did not take into account many of the factors involved in transfer. This is not a knock on him, but just the reality. Every legal decision applies only to its facts.
Subsequent scholars or judges apply these decisions, called precedents, to new and distinct factual situations. In other words, the Rambam's position will be looked at and weighed if this question ever comes up. So if and when that occurs, then the legal scholars can weigh all the facts and apply all the precedents. But until then, the question is merely academic.
I'm not saying we should ignore the Rambam. G-d forbid. His opinion is a precedent, like the past decisions of the Supreme Court. When the Court receives a question it does not just look at the precedent and apply it because the facts of the earlier cases are necessarily different from the facts in the case in front of it. Every case is different.