President Bush on Tuesday put forward another version of his argument that al-Qaida's role in 9/11 is the reason for the United States to continue the war in Iraq.

Speaking, again before a military audience, Mr. Bush was undoubtedly seeking to counteract growing pressure from a Congress where Democrats and disaffected Republicans are pushing disjointedly for a withdrawal timetable, and reacting to the most recent National Intelligence Estimate which portrays an unconquered, much reinvigorated al-Qaida chomping at the bit in Pakistan and Afghanistan.

The trouble was that the logic of Mr. Bush's argument was the same mix of fact and fiction regarding 9/11, al-Qaida and Iraq that got the United States into this war more than four years ago. His line runs something like this. Al-Qaida was behind the attack on the United States on Sept. 11. There is now fighting against U.S. forces in Iraq an organization that calls itself al-Qaida in Mesopotamia. Therefore, argues Mr. Bush, if the United States does not want to be attacked at home again as it was on 9/11, it needs to continue the war in Iraq.

There are big holes in his argument. First of all, al-Qaida in Mesopotamia did not exist when 9/11 occurred. It has developed in the past two years -- at most -- as the U.S. occupation and fighting in Iraq have continued. Iraq is now a prime training ground for Islamist fighters worldwide, rivalled only by Afghanistan, which the United States moved into far second place in 2002, and Pakistan.

Second, the link between al-Qaida "central" and al-Qaida in Mesopotamia is tenuous. Al-Qaida in general is a decentralized organization. The number-one objective of al-Qaida in Mesopotamia is to get the Americans out of Iraq, and, second, to see to it that Iraqi Sunnis get what they consider to be their deserved piece of the pie in post-war Iraq.

Therefore, whatever plans al-Qaida "central" may have for future attacks in the United States, al-Qaida in Mesopotamia presents a threat only to the 170,000 U.S. forces whom Mr. Bush insists on keeping in Iraq, more than 3,600 of whom have died so far.

The latest news that has seeped out of "Green Zone" Iraq in terms of what passes for planning in this administration has us there at least through 2009. There also continues to be talk of permanent U.S. bases in Iraq after the bulk of our forces withdraw, thus promising more U.S. casualties and continued taxpayer costs beyond the half trillion dollars -- about $2 billion a week -- spent so far.

The question then becomes whether Mr. Bush actually believes his own argument or whether the new line is just another chapter in the now five-year history of his attempts to bamboozle the American people on the subject of this war. Unfortunately, if he is allowed to proceed, America loses either way.