Reacting to partial intelligence is like diagnosing cancer without testing

It now seems that every government involved in the war on Iraq has begun to investigate the quality of the military intelligence which informed, or misinformed, its decision to launch the invasion.

I am no expert on military affairs; but during my career I have become familiar with medical testing and screening. I am also intrigued by both the making and breaking of codes, and the analysis and perception of risk. These other areas may hold some valuable lessons about the first.

Any military action will generate some retrospective analysis of the quality of the intelligence which preceded it. But politicians, and the public, should also be asking “What was the quality of the advice?” These are different questions which generate different answers.

Let me illustrate with a medical analogy.

An intelligence officer trying to find out what’s going on in some foreign and distant country shares many of the problems of the doctor who is trying to figure out what is going on inside a patient’s body. Both people must make important decisions on the basis of limited information, and both must assess the relative risks of a false positive and a false negative in making their diagnosis.

Imagine you have gone to your medical centre about a pain in your chest. Your doctor analyses the results of external examinations, scans, and laboratory tests. After the results are available, you are invited to come in for a chat. Your doctor tells you that the tests indicate that you might have a terminal cancer, but adds that the results are unclear, and it is in fact more likely to be something benign. The only way to be sure is to open you up for a closer look.

You dislike the idea of an operation, and ask for an assessment of the risk of it being the deadly cancer. Your doctor’s response is frank: “You would die – but at this stage we don’t believe this is a serious cancer.” You then ask about the risk associated with the operation itself, which the doctor assures you is “virtually nil”.

You are now facing the problem of uncertain “intelligence”. The health risk attached to a false negative (you reject the diagnosis and decide not to operate, when it is in fact a life-threatening cancer) is extremely high, while the risk of the false positive (you proceed to operate and find it’s benign) is very low.

What do you do?

I suggest that in these circumstances you would authorise the surgical “invasion”. You wake up from your operation to hear your surgeon confirm that the test was a false positive. You did not need the operation but you offer grateful thanks for “setting your mind at rest”, because it was worthwhile to learn that the feared tumour was never really there.

On the other hand, if your doctor had dismissed the test and not proceeded with the invasion of surgery, and as a result you died, your loved ones would probably sue.

Our newspapers are full of complaints about false positives. You hardly ever hear complaints about false negatives.

Military intelligence has faced this dilemma since the risks of war were first contemplated. Like the doctors, military advisers have had to assess the military strength of the enemy on the basis of limited information. The more different the culture, the more difficult it is to interpret the information.

Furthermore, the adversary is likely to send false signals. Sometimes they may want to persuade you of their weakness, to prepare the ground for a surprise attack. In recent times, potential enemies have tended to overstate their strength in order to deter attack. During the Cold War, the Soviets persuaded the West that their nuclear weapons and delivery systems were much more potent than they really were. The American Military had every reason to accept these exaggerated, or “sexed-up”, claims.

When the Cold War ended, we learned that the Soviet military “might” was more of a “mighty mouse”. Yet this “false positive” had helped to keep the peace, and finally brought down the Soviet Empire because the Americans kept upping the ante – and the costs of the conflict.

Conversely, military advisers who underestimate the strength of the enemy are normally pilloried by historians, who enjoy the benefit of 20/20 hindsight. We heap scorn on military advisers who refused to believe that Hitler’s panzer (armoured vehicle) divisions could cross Europe in a matter of days. Fortunately, the Germans in turn underestimated the strength of the British Air defences – and the power of radar in particular.

Now imagine you have been asked to advise the Bush and Blair Governments, post September 11, whether to invade Iraq.

You are peering into Iraq through a glass darkly.

You know for certain that Saddam’s regime has had a nuclear weapons program in the recent past, and used biological weapons to attack thousands of Kurds. However, you get conflicting signals about his access to weapons of mass destruction and have limited means of establishing the reliability of your sources.

A false positive (you conclude he has such weapons but it turns out that he hasn’t) means that a ruthless dictator is overturned, but the leaders of the Coalition of the Willing are pilloried by their political opponents, the Europeans, and Kim Hill. These risks are scary enough, but a false negative means that you may wake up to a phone call from Blair or Bush telling you that ten million New Yorkers and five million Londoners are now dead or dying, and you get pilloried by everyone with 20/20 hindsight, the Europeans, and Kim Hill.

And Saddam Hussein rules for a few more hours.

I suggest that in this case too, your advice would be the same as you gave your doctor – please invade, so that we know for certain. Quite simply, the risks of the false negative are far too great.

But unlike your doctors, neither Bush nor Blair will get any thanks for setting our minds at rest.

If I were in their shoes, I would now be pursuing two distinct but related lines of inquiry. First, was the quality of intelligence the best it could have been, and how might it be better next time? Second, did advisers give the right advice given the circumstances prevailing at the time?

The tragic reality of life is that the poorer the diagnostic quality of our medical tests, the greater the need to operate, and similarly, the poorer the quality of military intelligence, the greater the need to invade.

So what do we do about that?