Ever been to a builder’s house? Nothing is finished. The War on Terror is like that. The bathroom suite is in, but the tiling needs doing. The dining room has been knocked through but the plastering is a mess. And don’t get me started on the patio. We call what happened in Iraq a war, but in reality it was more of a distraction. We massaged the lie that Saddam Hussein could get a bomb here in 45 minutes, and lost sight of those that had cut out travelling time completely, by cooking one up in a bedsit in Beeston.

Builders get bored, I understand that. Spend all day doing something and you don’t want to do it again when you get home. Installing a luxury walk-in shower, now that might be a challenge. Plumbing, marble, fancy taps, the sort of stuff a chap can get his teeth into. But grouting? Yeah, love, next weekend, honestly. Don’t worry. I’ll get round to it, I promise. That is how our War on Terror ended up.

We were fine with regime change in Afghanistan. We even had a scout round the mountains for Osama bin Laden. Then someone mentioned Saddam and we were off before you could say elite Republican Guard. It was as if the painstaking daily process of identifying, seeking out and breaking up a terror network in all its minuscule factions was too much of a grind. We preferred shock and awe. Now we’ve got it.

Yes, say the pro-war lobby, but these terrorists would have attacked us whether we invaded Iraq or not. Absolutely. So, knowing this and identifying the danger, why did we then allow our resources to become diluted in the subjugation of a tangential dictator, whose military insignificance was such that within weeks he could be toppled and removed to a hole in the ground? Frankly, we could have taken Saddam out at any time. Yet with the postwar occupation a costly disaster, it is pertinent to question whether opening up this unnecessary second front in the War on Terror will not one day be recalled as the gravest tactical error of our lifetime.

Al-Qaeda is operative in Iraq now, yes. In August 1990, however, bin Laden was prepared to send his Mujahidin to Kuwait to liberate it from the invading Iraqi Army. These were not natural bedfellows. Even proven links between Saddam’s Iraq and al-Qaeda are small and tenuous, based around the odd rogue individual and a common enemy.

One prisoner at Guantanamo Bay is a former Iraqi infantryman, recruited by the Taleban, who became a member of al-Qaeda and was arrested in Pakistan in July, 2002. That same year, Ahmed Omar Saeed Sheikh, a former pupil of the fee-paying Forest School in Snaresbrook, East London, and a member of the Great Britain arm-wrestling team was sentenced to death for the kidnap and murder of the American journalist Daniel Pearl.

How are we to make sense of such random individuals? Iraq provided a safe haven for the al-Qaeda scientist who mixed the chemicals for the 1993 World Trade Centre attack; national television broadcast anti-Saudi propaganda and a confidant of bin Laden was a guest of Iraqi Intelligence in Baghdad for two weeks. We went to war over these odd facts while, under our noses, suicide bombers fermented in primary schools and youth centres. The War on Terror is a failure of imagination; alighting on a big bogeyman figure such as Saddam while letting a thousand little demons run free.

Those who spoke against the Iraq war were broadly satirised as the not-in-my-name lobby; but it was always a more complex argument than that. According to The Times last Friday, police believe that the mastermind behind the London bombings is linked to a senior al-Qaeda figure “. . . who took part in an al-Qaeda terror summit held in Pakistan 16 months ago”.

Did we miss a meeting? Apparently so. In March 2004, while this was taking place, 137,000 Coalition troops were present in Iraq, 30,000 in oil-rich Kuwait and just 20,000 in Afghanistan. If the Coalition, at that point, had chosen instead to take out al-Qaeda’s summer ball, it could have done so in my name, and in the name of a good many others, too. Bomb if you must; but make sure you drop them on the right people.

It is hard to believe that this week two years ago we were celebrating the triumph of 200 101st Airborne troops, an A10 Warthog gunship, several Kiowa and Apache helicopters and various Humvees armed with .50 calibre machineguns, over four people in a farmhouse near Mosul. The mission killed Saddam’s vicious sons Uday and Qusay and a bodyguard (and Qusay’s 14-year-old son Mustapha who, by an accident of birth, was the last man standing instead of at home learning French vocabulary, and was shot dead). Is the world a nicer place as a result? Probably, yes. Is it safer? Certainly no.

The argument advanced by the Royal Institute of International Affairs that Britain was made a priority terrorist target by war in Iraq, while plainly correct, also misses the point. Had the West and this Government done the right thing by pursuing al-Qaeda to the end, protecting its borders (the alleged mastermind of the bombings is believed to have flown out of the country the night before the attacks, as easily as he flew in to plan them) and criminalising the spread of hatred through religion as it now will, Britain would still have irritated enough people to be under some form of threat.

What is undeniable, however, is that our intelligence and military commitment to Iraq has made us less able to police that threat, that the threat has grown as a result of the diversion and that our overstretched foreign policy has left us playing catch-up. For this reason, the British people now live in an archetypal builder’s house. It looks like a bomb’s hit it.