QALQILYA, West Bank

If there is one iron law that has shaped the history of Arab-Israeli relations, it's the law of unintended consequences. For instance, Israel is still wrestling with all the unintended consequences of its victory in 1967. Today, Israel is building a fence and walls around the West Bank to deter suicide bombers. But, having looked at this wall extensively from both sides, I am ready to make a prediction: It will be the mother of all unintended consequences.

Rather than create the outlines of a two-state solution, this wall will kill that idea for Palestinians, and drive them, over time, to demand instead a one-state solution — where they and the Jews would have equal rights in one state. And since by 2010 there will be more Palestinian Arabs than Jews living in Israel, the West Bank and Gaza combined, this transformation of the Palestinian cause will be very problematic for Israel. If American Jews think it's hard to defend Israel today on college campuses, imagine what it will be like when their kids have to argue against the principle of one man, one vote.