I'm not saying this UN vote alone increased the chances of terrorism by much. In fact, it increased them by only a very tiny bit. But that's more than zero, and every increment matters. And, however tiny the increment, it was only increased when Netanyahu then turned around and announced an epically indefensible settlement project; America, especially after its display of loyalty to Israel at the UN, is naturally seen as complicit in things like that. (And, no, toothless diplomatic protests by the US don't do much to change that perception.)

So Obama needs to stop this settlement project--not just to save face, but to protect Americans. He needs to show Arabs and Muslims--and everybody else--that no nation, including Israel, can take America's support completely for granted; that America won't stand by impotently as Israel embarks on a project that shows contempt for the Palestinian people and for world opinion.

Obama's leverage with Netanyahu is limited, because Congress has so much influence over purse strings. But the president has enough leverage to do what needs to be done. Here's how he should proceed:

[1] Write out a statement that he's willing to deliver on TV. It should criticize Netanyahu sharply and say something that will shock the Israeli people: If the prime minister is going to behave this outrageously, America can no longer guarantee that it will stand by Israel's side at the United Nations. It can no longer guarantee that it will veto Security Council resolutions that declare West Bank settlements in violation of international law. Indeed, America may now introduce such a resolution--that's how outrageous this latest settlement project is.

[2] Call Netanyahu, read him the statement, and tell him that if the settlement plans haven't been reversed within 48 hours, Obama will deliver the statement on TV.

And Obama has to mean it. He has to be ready to deliver the statement--because then Netanyahu will sense that he means it, in which case Obama won't have to deliver the statement.

The Israeli people care very much about their relationship with the United States--especially when so much of the world is rejecting their policies toward the Palestinians. So Netanyahu doesn't want to head into the coming election as the prime minister who has done more to jeopardize that special relationship than any Israeli leader in memory. He'll cave.

He'll hate caving, because he'll look foolish, and the whole episode will have hurt him politically. But it won't hurt him as much as something approaching an actual breach with the United States.

And if for some reason he doesn't cave, and Obama has to deliver his statement, I predict that Obama will find--to the surprise of many--that he pays no significant political price (or, at most, a price that a second-term president can easily tolerate). The reason is that pretty much everyone who's paying attention to this issue realizes how indefensible Netanyahu's behavior has been. Most people will realize, too, that Obama is acting in Israel's best interests by trying to strongarm it into limiting its alienation of the world.