It would be understating the case to suggest that in accepting a role as the quartet’s special envoy to the Israeli/Palestinian problem Prime Minister Blair will have his work cut out for him. America, the European Union, the United Nations, and Russia — the so-called quartet — are set to announce today that Mr. Blair will be the new envoy, although there is some question about how broad a mandate they will give him. Mr. Blair is a player on the world stage in his own right, and some members of the quartet may come to resent the large shadow he will inevitably cast. Javier Solana, the EU’s top foreign policy official, is already bellyaching that Mr. Blair’s mission will sideline his own Mideast peace efforts. Russia successfully de-compartmentalized its difficulties with Mr. Blair over the continuing investigation into the assassination of Alexander Litvinenko in London.

Expectations are bound to mount, notwithstanding attempts to circumscribe the scope of Mr. Blair’s brief. A senior official in the Bush administration told the Associated Press yesterday that Mr. Blair will work on more than Palestinian “economics,” but that he “should not be mistaken as a mediator or negotiator.” That’s a slight encouragement; the last thing we need is a negotiator, particularly because the pressure to compel the parties to reach a settlement may reach a feverish pitch. At the same time, the likelihood of such an arrangement has never appeared more remote. Mr. Blair erred yesterday, when he said that “a lasting and enduring resolution of the Israeli-Palestinian issue is essential” to “greater peace and stability in the world.” It’s an erroneous view, even if the notion that world peace depends on the establishment of a Palestinian state is so widespread that those who question it are dismissed as rudely as global warming skeptics.

Not only does that notion place an enormous and unjustified burden on Israel, but it does not look like the Palestinians are anywhere near capable of playing the role the international community has envisioned for them. So the internal logic of Mr. Blair’s appointment will be to press Israel to generate sufficient concessions to allow President Abbas to succeed. It is telling that Prime Minister Olmert, sensitive to the slightest tremor in his ties to the Bush administration, is more inclined to allow arms shipments to Mr. Abbas’ forces than is the leader of the putatively more dovish Labor Party, Defense Minister Barak, who makes the point that the problem with the Fatah forces is “motivation” not insufficient arms. This is the context in which Israel’s opposition leader, Benjamin Netanyahu, suggested that Jerusalem permit the introduction into the West Bank of the Badr Brigade, a Palestinian unit of 5,000 men under the command of the Jordanian army.

Mr. Blair is available because he is stepping down as premier after a long and successful run in which he risked his political career by partnering with America in Iraq. Mr. Bush has the advantage in that his supporters remain committed to the fight against Islamic terrorism. By contrast, Mr. Blair’s base split almost at once over the Iraq decision. Anti-war protesters marching in Washington were not Mr. Bush’s voters. Anti-war protesters marching in London were Mr. Blair’s voters. Mr. Blair’s clear sightedness in the matter of Iraq came with a price for Israel. Back Mr. Bush on Iraq and influence America on the need to resolve the Palestinian question became one of Mr. Blair’s answers to the anti-Iraq war left within his Labor Party. There will now be cognitive dissonance between the mighty expectations that will accompany the appointment of a man of Mr. Blair’s stature, and the decay and dissolution within Palestinian ranks.