Former Secretary of State Henry Kissinger was yesterday named by President George W. Bush to head an independent commission to investigate the September 11 attacks, and the failure of United States intelligence services to detect the worst terrorist outrage in US history.

Bush said the commission would help the US understand the minds and methods of its new global enemy. The investigation "should carefully examine all the evidence, and follow all the facts wherever they lead".

The commission will have a broad mandate, building on work already done by a joint House and Senate committee. It has 18 months to do its work, though Bush would like to have a report earlier.

"The sooner we have the commission's conclusions, the sooner this Administration will act."

In fact, the President long resisted a September 11 inquiry, maintaining that its broad subpoena powers could lead to embarrassing leaks and interfere with the war against terrorism.

Bush was forced to bow to intense pressure from the families of the victims after increasing evidence of the shortcomings of the FBI, the CIA and the National Security Agency, and their inability to co-operate.

But he has insisted that the commission be bipartisan.

Its 10 members will be appointed by Bush and be equally split between Republicans and Democrats. At least six members will be required to approve a subpoena, to ensure that witnesses are not called merely to score party-political points.

In these circumstances, Kissinger is an obvious choice.

Although his manipulative style and ruthless realpolitik under Presidents Nixon and Ford have made him something of a demon for liberals, he is hugely respected.

For most Americans, Kissinger's role in the Vietnam war and US support for brutal military regimes in Chile and elsewhere have been forgotten. For them, the 79-year-old is above all the Nobel Prize-winning co-architect with Nixon of detente with the Soviet Union and China.

Kissinger's brief is far-reaching.

"We are under no restrictions and will accept no restrictions," he said on his first return to Government service in a quarter of a century.

The probe could be explosive. Not only will it explore how much was known by Government agencies and their failure "to connect the dots" pointing to an impending attack on the US, but it can also hardly avoid the foreign support for al Qaeda from US allies such as Saudi Arabia and Pakistan.