But building has also continued in smaller settlements beyond the fence—the strongholds of the settlers most committed to permanent Israeli rule of the West Bank. They have taken the initiative in expanding their communities. But they also enjoy backing from within the civil service. The Housing Ministry, for instance, still provides subsidized mortgages for homes in such settlements. An entrenched bureaucratic culture trumps orders from the top.

Olmert lacked the strength to crack down on that bureaucracy or risk confrontation with the settlers. Of his potential successors, Benjamin Netanyahu is the candidate of the pro-settlement right, and Tzipi Livni, the candidate of Olmert’s Kadima Party, has shown no signs that she is willing or able to stop the building in the absence of a peace deal.

The settlers’ growing power makes it harder for any Israeli leader to act. The head of the Shin Bet security agency recently described “very high willingness” among settlers “to use violence—not just stones, but live weapons—in order to prevent or halt a diplomatic process.” He was articulating a country’s half-spoken fears: Withdrawal involves more than the social and financial costs of moving hundreds of thousands of people. It poses the danger of civil conflict, of battles pitting Jews against Jews.

The more settlers, the greater the danger. The longer the wait, the more settlers. The more settlers, the more hesitant politicians are to talk about evacuating them, much less do anything else about them. It’s anybody’s guess where the point of no return lies.

But there are no good alternatives to pulling back. Olmert’s plan to redraw the borders, with fingers of Israeli land extending to major settlements, would slice up Palestinian territory, while the smaller, more radical settlements would need to be evacuated. Some observers still cling to a one-state solution—a fantasy held by those who believe that nationalism is about to fade away. Such a state would teeter between communal violence and mere political deadlock as Jews and Palestinians would try and fail to form a stable government.

So, time is in short supply. As U.S. President Barack Obama enters office, he might be tempted to put off dealing with the Israeli-Palestinian conflict. But delay may mean finding the road to a solution closed. The alternative is to exert pressure on the Israeli government to freeze settlement—and then move quickly toward a final-status agreement.

Of course, the greatest responsibility falls on Israeli leaders. The next prime minister will have the choice of learning from Olmert’s unfulfilled pledge or repeating his failure to act. If Israel is to withdraw from the West Bank, the essential first step is to order an immediate stop to settlement construction. Confronting the settlers will require great courage. Yet failing to do so risks Israel’s existence as a Jewish state. That’s the lesson written on the hills.