The crucial question regarding Iraq is not whether the motives for war were disguised, but why. The argument that Iraq posed a grave and imminent threat was absurd to anybody not under the spell of round-the-clock White House and 10 Downing Street spin. But the actual reasons for launching the war remain obscure. The plot thickened with the release last month of the US Congressional investigation into September 11. It seems increasingly likely that Iraq was attacked because Saudi Arabia was deeply implicated in the terrorist attacks.

Two truths have long governed US energy security. The first is that Saudi Arabia is the key to world oil stability, the accommodating supplier when markets get too tight. It would be a potential threat to the world economy if Saudi oil flows were disrupted. In 1973-74, with the Arab oil embargo, the Ford presidency was brought down by the disruption of the US economy, a point not lost on two young senior officials at the time, Donald Rumsfeld and Richard Cheney, respectively Gerald Ford's defence secretary and White House chief of staff. Pentagon and academic planners began making contingency plans for the military seizure of the Middle East oilfields.

The second truth is that Saudi Arabia has been a spigot of private wealth for key US figures, and for the Bush extended family in particular. The Saudi royal family lacks political legitimacy at home, so it buys US protection from abroad. The Saudis purchase Washington influence through consultancy contracts, big defence outlays on US military hardware, lucrative speeches for Washington insiders, investments in US businesses with influential figures, and the like. A long line of US senior officials has benefited, with the Ford, George H.W. Bush and George W. Bush White House and Pentagon at the front of the line. Saudi business has helped to make multi-millionaires of Henry Kissinger, Frank Carlucci, James Baker, George H.W. Bush, Mr Cheney and dozens of other insiders.

September 11 threatened these two truths. Within hours of the attack, the White House apparently understood that senior Saudi intelligence officials

were probably involved and that 15 out of the 19 terrorists were from Saudi Arabia. They were no doubt stunned to realise that parts of the vast Saudi royal family were not only corrupt, but also deeply intertwined with anti- American terror and extremist fundamentalism. A new book by former CIA agent Robert Baer, Sleeping with the Devil*, details how the US government had systematically turned away from the growing evidence of Saudi complicity in fundamentalist terrorism, thereby frustrating the kind of investigations that might have headed off September 11.

To say that Saudi complicity in September 11 led the White House to war in Iraq is speculative, but several insiders have suggested that the conflict was incubated, perhaps hatched, in the immediate aftermath of the attacks. There are at least four plausible channels that together might explain the speed with which the decision on Iraq was taken after September 11. First, September 11 was a dramatic confirmation that the stability of Saudi oil was in jeopardy. The regime was unstable and perhaps even a lethal threat to the US. The only quantitatively significant alternative to Saudi oil was Iraqi oil, but that option was barred as long as Saddam Hussein remained in power. The long-standing contingency plans to seize Middle Eastern oil were probably rolled out within days of September 11.

Second, a substitute had to be found for the US military bases in Saudi Arabia. Like Saudi oil, the bases too were now under threat, especially because the US presence in the Saudi kingdom was known to be the principal irritant for al-Qaeda. Iraq would become a new base of US military operations. Paul Wolfowitz, deputy defence secretary, has already explained during an interview with

Vanity Fair that Iraq's weapons of mass destruction were but a bureaucratic pretext that hid other core motives for war, including the reduction of the US military presence in Saudi Arabia. Mr Wolfowitz's remarkable statement seemed bizarre at the time it became public but was allowed to pass in the US without scrutiny. But it makes full sense in the context of a White House debate about the US's response to a teetering Saudi regime.

Third, the Bush White House needed to issue a powerful threat to the Saudi leadership: one more false step and you're finished. Attacking the next-door neighbour was no doubt judged to be quite persuasive. A direct diplomatic attack was probably ruled out by the deep and inextricable links between the White House and the Saudi leadership. Finally, there was probably a strong

hope that the public could be diverted from the true roots of September 11. The Bush administration needed to turn the public's eyes away from the intelligence failures and head off the danger, however slight, that Saudi associates of the Bush family and friends would be implicated in the attacks. Mr Hussein was the perfect target: a true despot, long-standing public enemy of the US and a wastrel of energy resources needed by US consumers.

Perhaps the Iraq war had roots other than September 11 and Saudi Arabia. There is even a tiny, if fading chance, that the ostensible motive - weapons of mass destruction - had merit. But if the Iraq war was an opportunistic response to September 11, it is crucially important that we know it. Thousands of lives and perhaps Dollars 100bn have gone into this war, with little to show for it except an enraged Iraqi public and enormous costs of occupation extending into the future.

The US media have so far shown little interest in connecting the dots. Meanwhile, the administration continues to play on the public's post- September 11 fears and its pride and comfort in US military might. Yet the questions do not fade away. The administration's seeming unwillingness to examine the Saudi connections and the enormous costs of Iraqi occupation are now causing concern even among the president's stalwarts in Congress. The issues are too big to be swept aside, even by the powerful currents of patriotism, fear and spin.

* Sleeping With the Devil: How Washington Sold our Soul for Saudi Crude, by Robert Baer (Crown Publications) The writer is director of the Earth Institute at Columbia University

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