Dear Tony Blair:

Why did you do it?

Why did you accept the post of special Middle East envoy for the Quartet (the United States, European Union, United Nations and Russia) just after stepping down as prime minister?

Can’t you see that this appointment – promoted by the White House and Condi Rice – is designed to fail?

Clearly, you don’t want your legacy to be defined by the Iraq war. You believe that progress in the Israeli-Palestinian peace process would undercut radical Islamists. You’ve been frustrated at your inability to persuade George Bush to do more to promote that process than make nice speeches.

Still, unless you redefine this job and get White House support, you’ll soon be immersed in another Mideast debacle. The problem with this post is you have no power to make a difference. The mandate is so narrow as to be a joke.

According to State Department spokesman Sean McCormack, you’ll be limited to helping Palestinians rebuild their economy and institutions in the West Bank. (Presumably your mandate won’t extend to the Gaza Strip, which is controlled by Hamas.)

The purpose of your post, says McCormack, is to ensure that, if a Palestinian homeland is created, it will be able to function as a “well-governed state.” No question, Palestinian institutions are rife with corruption and need reforming. But the West Bank is not a petri dish. Surely, you observed in Iraq that Westerners have trouble conducting social experiments under conditions of occupation and violence.

The West Bank today is under tight Israeli security restraints that make it virtually impossible for any Palestinian economy to function. As I witnessed on a recent trip, entrance and exits from most villages and towns are closely controlled, and many roads are blocked by checkpoints. Palestinian areas are cut off from one another by a combination of Israel’s security fence, roads limited to Israeli settlers, land controlled by the army, and settlements.

Farmers cannot get their produce to towns, and towns cannot get their goods to market. The Palestinian economy is frozen, and the population depends on foreign aid.

Bush officials have repeatedly called for a relaxation of these blockages. But, despite the lifting of some checkpoints, Israel has argued its security demands continuation of most closures.

Your mandate, Mr. Blair, does not include any charge to deal with these security issues. So how can you deal with Palestinians’ economic problems? And how can any Palestinian government operate when its officials often cannot travel beyond their town?

Moreover, these security issues cannot be addressed without looking at the bigger political picture. Palestinians do care about corruption. But their main concern is whether they have any reason to hope for a better political future.

Unless Palestinians can see a clearer “political horizon,” meaning the outlines of a state, they won’t turn against violent groups. One big reason Palestinians voted for Hamas in the 2006 elections was that the opposition Fatah Party – seen as the party of negotiations – couldn’t engineer a resumption of peace talks.

But your mandate, Mr. Blair, does not include the authority to try to bridge Israeli and Palestinian positions on the bigger political issues. If you are prevented from dealing with the big stuff, you will fail on the smaller (though important) issues.

Surely you are aware of what happened to your predecessor as Quartet envoy, James Wolfensohn, former president of the World Bank. He quit the post – which focused on improving the Gaza economy – in frustration.

Wolfensohn was bitter that he couldn’t get Israel to facilitate Palestinian exports from Gaza; Israelis shut border cargo crossings for security reasons, despite U.S. efforts to fund upgraded scanners to check cargo containers.

Wolfensohn argued that facilitating Gaza exports would have created jobs. This, in turn, would have undercut the appeal of Hamas in Gaza, where the Islamist group runs popular welfare organizations. He urged Israel to look at the bigger picture. But he had no power to impress that point on Israeli officials. While Bush talked of building a model democracy in Gaza, U.S. officials failed to help.

So how can you, Mr. Blair, expect to work miracles in the West Bank? As former Mideast envoy George Mitchell said: “It’s going to be very difficult to get the Palestinians to move when (Blair) has no authority to get into the broader issues which are somehow on a separate track run by others.” Mitchell has much experience with these matters, having helped you broker a 1998 power-sharing agreement between Protestants and Catholics in Northern Ireland.

Perhaps you, too, Mr. Blair, need to refer back to the lessons of the Northern Ireland peace pact, one of your proudest achievements. In that case, the untiring participation of the British and Irish governments, for years, was key.

Unless the White House (and Quartet) are ready to immerse fully in a peace process, and to persist until the Israeli-Palestinian gap is bridged, you’re on a losing tack, Tony. The process would have to involve moderate Arab states, too. If the Quartet makes you their envoy under those conditions, the post is worth taking. Otherwise, you’d better find another cause to take up your retirement years.