Every which way, US President George W. Bush is trying to send a signal, as he heads to the region this week, that he is with Israel and with the Arab states that feel threatened by Iran. To Army Radio he said, "If Iran did strike Israel... We will defend our ally, no ands, ifs or buts." To Gulf journalists, he said he expected leaders to ask him, "Will we be working with friends and allies on developing a security plan?" Bush's answer was: "Absolutely, we will be. That's one of the main purposes of the trip, to talk about US commitment to the region." All this sounds, on one level, reassuring, but on another, frightening. The fact that Bush is traveling here to show his support and commitment to Israel and the region must not be minimized. The gesture is significant and appreciated. But Bush himself is a leader who presumably understands that it is the bottom line that matters, and that line is a simple one: Will Iran be allowed to go nuclear or not? What does it mean, for example, to develop a "security plan"? No amount of arms sales, basing commitments or new defense pledges will be sufficient to counteract the impact of a nuclear Iran. Bush himself described the problem in his radio address on Saturday: "As we saw on September the 11th, 2001, dangers that arise on the other side of the world can bring death and destruction to our own streets. Since then, extremists have assassinated democratic leaders from Afghanistan to Lebanon to Pakistan. They have murdered innocent people from Saudi Arabia to Jordan and Iraq. They are seeking... [to] attack America again, overthrow governments in the Middle East, and impose their hateful vision on millions." America has the greatest army and nuclear force in the world. Yet it was vulnerable to terrorism. Similarly, no "security plan" will protect the states of the region against a jihadist front that has just acquired a nuclear umbrella from a jihadist power. In the same vein, as important as it is to hear that America would help defend Israel if it was attacked, again, what does this imply? Does this mean that the US is coming to terms with the prospect of a nuclear Iran? This newspaper previously suggested that the most reassuring thing Bush could do would be to stop in London, Paris and Berlin on the way to Israel to demonstrate that the talk of strengthening sanctions against Iran was not just lip service, but America's central foreign policy priority. Judging from the travel schedules of Bush and his secretary of state, the top US priority is Annapolis, not Iran. This is backwards, and until these priorities are reversed, no amount of hand-holding will assuage the concerns of Israel and the more moderate Arab states. So long as the leaders of the region suspect that the US has deluded itself into thinking that Annapolis is a substitute for confronting Iran, none of them will take Annapolis seriously, nor will they take any risks to make Annapolis work. Why risk angering Iran and its armies of suicide bombers when it seems evident that the US has no plan for and little prospect of stopping Iran from going nuclear? True, for years it was convenient for Arab leaders to pretend that they could do nothing until Washington solved the Arab-Israeli conflict for them. But with the threat from Iran looming, these same leaders are appalled that the US seems to have built its policies according to their public facade, rather than based on what really concerns them. US National Security Advisor Stephen Hadley said one purpose of Bush's trip is to "encourage broader Israeli-Arab reconciliation." Pushing Arab states to normalize relations with Israel is indeed a critical objective and something that Bush has repeatedly called for, but the Arab states won't deliver unless they see that the US is making real progress against Iran. This, indeed, is the grand bargain that Bush should propose to Arab states: a serious US sanctions campaign - backed by a Bush visit to Europe - to isolate Iran in exchange for greater Arab gestures toward normalization with Israel. Such a deal would help the US convince Europe to impose tougher sanctions, help the Palestinian Authority against Hamas and increase American prestige, and it could help turn the tide of inevitability away from an Iranian bomb. Bush should make clear: Annapolis depends on isolating Iran, so anyone who says they want Annapolis to work - as have Europe and the Arab states - needs to join in dramatically tightening the screws on Teheran.