How do you ask a man to be the last man to die for a mistake? Faced with a government whose only response to the hole that had been dug in Vietnam was to bring in bigger shovels, the question John Kerry asked a Senate committee in 1971 was meant to be rhetorical. Three decades on, another time, another hopeless war, George Bush has provided an answer. You do it from the White House library.

The switch from the Oval Office was done to lend the broadcast a more relaxed air, yet the visuals clashed badly with the verbals from the off. The row upon row of weighty tomes behind him whispered "man of learning"; the words coming out of his mouth shrieked "dunce". This was a President who not only seemed devoid of any sense of irony but of history, especially his own. After announcing the sending of an extra 20,000 US troops to Iraq, he said: "Victory will not look like the ones our fathers and grandfathers achieved," he said. "There will be no surrender ceremony on the deck of a battleship." You would think a man haunted by images of himself standing in front of a banner declaring "mission accomplished" would have steered clear of nautical imagery, but that would be to betray your membership of what a Bush aide once called "the reality-based community".

To a neocon way of thinking, reality is something that happens while you are busy making other plans. Despite some novel words of contrition in the President's statement, the basic message was the same: the US will stay the course because walking away from a fight abroad makes it more likely terrorists will strike at home.

Being on the safe side against terrorism means putting Iraqi civilians, and the forces meant to be protecting them, further into harm's way. The new mission, which sounds remarkably like the old one, is to "clear and secure" neighbourhoods of insurgents. Sounds a reasonable idea until you factor in some of that irritating reality the neocons so dislike. The mainly Shia Iraqi security forces already stand accused of ignoring or assisting in attacks on Sunnis. For them to enter Sunni communities after US forces have paved the way with aerial bombing will fuel sectarian tensions further and make the US appear to be taking sides in a civil war.

The assumption that rings of steel can be thrown round areas and insurgents contained until they surrender or die doesn't sit well with reality, either. It has been plain from the moment US forces entered the country that the resistance to them is highly mobile and embedded within the civilian population. It does not give up, it simply moves on. In this case, it is likely to move on to British- controlled Basra. Taking an even hand with insurgents, as the US President says the Iraqi government will do from now on, means tackling and defeating Moqtada al Sadr. The US, despite the firepower it threw at the problem, was unable to do this in 2004. Three years on, the Mehdi army, reckoned to be 30,000 strong then, is bigger and better armed.

While the strategy of "clear and secure" unfolds on land, US aircraft carriers, their number bolstered by the President in his speech, will be observing from afar. Their job, in turn, will be to keep an eye on Iran and Syria. Far from bringing the neighbours on side, as the bipartisan Iraq Study Group advised, the President has put them on notice that they, too, are on a final warning.

What a Strangelovian soup Mr Bush has lit a fire under. There are some, most of them in the White House, who persist in seeing a method in the madness. Their argument starts and ends with the belief that defeat for the US would be a bad thing. The reality, that defeat has already occurred, has not yet penetrated. The President was right in one sense. Victory in Iraq won't look like the ones of the past century because there is no victory to be had, only degrees of defeat.

If the President liked the ambience of the White House library, he should spend more time within its rose-tinted embrace. When he tires of admiring the late Federal period furnishings, he might like to peruse the transcripts of past presidential addresses to see how his predecessors assured the nation in times of crisis. One speech in particular might strike him as familiar. Like his address, it referred to the cleaning out of "enemy sanctuaries", expanding a war in order to win it, and the absolute importance of the US standing firm and not accepting defeat. The President was Nixon and, as is now known, what he was telling the American people about Cambodia was only a fraction of the truth. The current President has made his intentions only too plain, and he has done so in the face of opposition from Congress, the American public and much of the world. There is no comfort to be had from his honesty, only a wretched sense of foreboding.