Mr Obama's tough job this week just got that much tougher. To put it crudely, the question he has to address is: "When Israel kills demonstrators is that the same as when Syria or Libya does the same?"

For a long while the White House has been hinting at a big foreign policy big speech about the region. Initially it was thought of a new Middle East peace initiative. With things looking grim on that front it was downgraded to little more than getting his punches in first, before Israel's prime minister speaks to Congress at the end of the week. It was saved from being a contest with Bibi by Bin Laden's killing. This allows Obama a more panoramic sweep around the Middle East.

Doubtless his main theme will be that the Arab Spring is diametrically opposed to Bin Laden's ideology, and leaves al-Qaeda looking flat footed and out dated. With language that recalls the civil rights movement, he will back peaceful demonstrations for democracy and contrast them with violent actions for autocracy. In Egypt, Libya, Tunisia, Bahrain and Syria, no-one is burning the stars and stripes. He may or may not spell it out, but there is an underlying sense from this White House, as much as the last, of that contradictory feeling that American exceptionalism is a worldwide export. Obama is likely to note that most of the demonstrators don't want to destroy the values that America and the West cherish, they want more of them.

That's fine as far as it goes. I've noted and you've discussed, many times on these virtual pages, that not all countries are treated the same. Mr Obama put himself on the side of the Arab Street in Egypt. Eventually. He was hesitant about intervention in Libya. But America has taken military action to protect the protesters. There are no sanctions against Syria's President Bashar al-Assad. Many are bewildered by that. The words are always pro-reform, pro-democracy. But the rulers of Bahrain and Yemen get a stern ticking off when their security forces kill demonstrators, not bombs aimed at their homes. In Saudi Arabia there has been little trouble. For small mercies, the White House must be thankful. A Saudi revolt would scatter the house of cards, that is Washington's unquiet melange of realpolik and progressive morality.

But Saudi is not really the elephant in the room. We will find out on Thursday if Mr Obama makes the point that some are now arguing, that Israel does not stand outside the region, outside the arc of history, outside the change that is going on. Does he praise it for being the only real democracy in the area? Does he condemn it for killing protesters? Let's face it, for years when policy makers and journalists have said "the Middle East" they've meant the Israeli-Palestinian conflict. Mr Obama believes that solving it is a key to better relationship with Muslims and the Arab world. But Mr Obama is distrusted in Israel, has no viable plan, and has just lost the ever-patient George Mitchell as his envoy. He has to say something on the "peace process" and we all wait agog for any news-making pronouncement. But he needs some sort of super sat nav, because the road map isn't working, whichever way you hold it up.

I have said in the past, rather complacently, that no president gets poor marks for failing to make peace in the Middle East. But how Mr Obama handles this is critical, and it is hard to know what proposals or rhetoric would make his speech soar above the obvious, and into history.