Rupert Cornwell: A bombshell that intensifies the pressure on Bush

Seen from the cratered, violence-drenched reality in Baghdad, the conclusions of the ISG might appear as theoretical musings from a far-away land. In the often unreal world of Washington politics however, the bipartisan panel's report is a metaphorical bombshell. It hugely intensifies the pressure on an already weakened George Bush to change course on the issue that will define his Presidency - or leave him more isolated than ever.

The report calls into question the administration's entire Middle East policy: not just its failure in Iraq, but its attitude to the Palestinian/Israeli conflict, its approach to the Lebanon/Syria crisis, and its relations with Iran.

And this closely reasoned, withering critique comes not from what the White House would regard as the usual suspects, such as Congressional Democrats or the editorial columns of the New York Times.

Instead, it has been delivered from the summit of the permanent Washington establishment, by a 10-member panel of the great and the good, drawn from Democratic and Republican ranks - who moreover reached their conclusions with remarkable speed and unanimity.

As a result, Mr Bush will not be able to claim this is a conspiracy of his critics. But now Republicans who disagree with him will find it far easier to break ranks. For Mr Bush, the trickiest part of the report is that dealing with regional diplomacy. Its calls for US troop withdrawals and beefed-up training of Iraqi security forces, with the underlying theme that Iraqis must take charge of their destiny, are shared by almost everyone.

Mr Bush would like to draw down the troops as much as his critics. But even these latter know that a precipitate withdrawal could well make matters worse - and the ISG declares as much. But the speedy direct engagement with Iran and Syria recommended by the panel is another matter.

Thus far the President has steadfastly refused to so, linking dealings with Syria to its conduct in Lebanon, and insisting that before talks with Iran, the Teheran regime must suspend its uranium enrichment programme.

James Baker, Secretary of State for this President's father and the Republican co-chairman of the ISG, gave short shrift to this approach at yesterday's press conference launching the report, noting that, "We talked to the Soviets for 40 years, when they were trying to blow us up." It is not a sign of weakness to talk to your adversaries, Mr Baker stressed again.

Instead the ISG suggests the nuclear confrontation with Iran should be dealt with at the United Nations, and urges the administration to launch a comprehensive regional push, or "New Diplomatic Offensive," before the end of the year.

The administration says that the ISG report is just one among three sets of recommendations on the President's desk, along with reports drawn up by the Pentagon and the White House itself. The administration would like to play for time. But the ISG's message is that time is running out - if it has not run out already. If Mr Bush goes the ISG route, he is looking at a very busy Christmas.

But will he go that route? That is the unanswerable question. Bipartisan co-operation is essential if a coherent Iraq policy, that enjoys public support, is to emerge. But Mr Bush has shown no inclination to do so.