Last Tuesday was World Mental Health Day and in this country a couple of attention-seeking politicians have been holding forth about mental illness, which is what the phrase mental health now means.

David Blunkett, in his self-pitying diaries, confessed that while a cabinet minister he had been “clinically depressed” during his deluded affair with a society minx. Alastair Campbell shared with the nation his experiences of a psychotic breakdown in the 1980s, when he was arrested for driving the wrong way round and round a roundabout and sent to hospital, and also his deep depression in Downing Street at the time of Dr David Kelly’s famous suicide.

This only confirms one’s worst fears that new Labour has for a long time been in the grip of a collection of unstable chancers. One only has to think of the neurotically disabling mutual loathing of Tony Blair and Gordon Brown.

I had not realised that Campbell was subject to periods of depression, still less that he had suffered a psychotic collapse. I had only known he was an alcoholic. But his revelations do a great deal to explain his alarming behaviour when in power. Reports of his conduct constantly suggested extreme aggression, paranoia, ill-controlled anger and an eccentric attitude to truth, which one might expect of someone prone to mental disorder. The deep depression he described at the death of Dr Kelly can only, for someone in Campbell’s awkward position, be seen as normal. Otherwise one can all too easily appreciate that he may suffer intermittently from mental illness.

Blunkett’s claim to “clinical depression” is less easy to accept. It is hardly surprising, in a painful intrigue with a married woman, involving a disputed baby or two and a huge threat to one’s political ambitions, that a man might feel a bit low. That would be normal. But this phrase “clinical depression” is thrown around too vaguely, and indeed its meaning is rather vague.

The truth is that anything more than mild to moderate depression is seriously debilitating. It would involve, among other things, a sense of futility and self-loathing, impaired judgment, impaired relationships with other people, mild paranoia, a loss of drive and energy, indecisiveness and chronic fatigue, precisely what one would not want in a cabinet minister, or a surgeon or head teacher for that matter.

Perhaps Blunkett did not feel quite as bad as all that. After all, he says he refused the offer of antidepressant pills. But if he was more than mildly depressed, he should certainly have resigned or have been told to stand down, and so should Campbell. People in the grip of mental illness can’t function properly. They should most certainly not be doing extremely responsible and demanding jobs.

Yet both Blunkett and Campbell have praised Blair for being so understanding about their mental problems and enabling them to go on working. Indeed, in Blunkett’s account Blair seemed to think that being a cabinet minister might be good occupational therapy for his old friend — not perhaps the best use of one the great ministries of state. Blunkett and Campbell, like Stephen Fry in his television series on mental illness, have said they have spoken out because they want to help remove the stigma of mental illness; that is after all the point of World Mental Health Day.

Ironically, the efforts of Campbell and Blunkett confirm my sad belief that the stigma is useful. It warns us, however crudely, of the dangers mentally ill people often present to themselves and others. What Blunkett, Campbell, Fry and others are expressing is the current orthodoxy: people with mental illnesses must not be subject to any kind of discrimination, least of all at work.

I cannot agree. Of course unfair or undue discrimination is wrong; and of course it is true that until very recently people’s attitudes to mental illness were brutal and ignorant. The lunatic asylums of my childhood were often places of horror and there was a tendency to assume that everyone who was a bit “mental” could turn into a homicidal loony. Even now people can be very cruel. But that is no reason to go into denial, covering up painful realities with soothing euphemism.

These days you hardly ever hear the phrase mental illness, at least not in public sector and right-on circles. People almost always talk instead of “issues around mental health”. Illness bad, issues okay. This is quite absurd; it is as if an alcoholic were to talk of “issues around sobriety”. There are no issues about sobriety. The issue is alcoholism, or mental illness.

Campbell pointed out that six out of 10 employers say they wouldn’t take on someone with mental health problems, as if that were self-evidently unfair.

Baroness Neuberger wrote to The Times saying: “There is no reason why having a mental health diagnosis (sic) should stop a person working, at any level. With the right support and good management, people with mental health problems can work as well as anyone.” Yet, she continued, myths abound, “making employers wary of keeping, let alone hiring, those with mental health conditions (sic)”.

No doubt myths do abound, but one of them is that mentally ill people are all just as employable as everyone else. They aren’t.

Those with mild, intermittent problems may be able to hold down certain, but not all jobs, with help and understanding. They may not present much of a problem to their employers, or they may choose self-employment to keep their problems to themselves. But people suffering from anything worse are clearly a liability to themselves and others.

Anyone who has known people with bipolar disease, chronic acute anxiety or severe obsessive compulsive disorder, to pick just three common “conditions”, will know that these people’s lives are a constant struggle. I have nothing but sympathy for them. There is plenty of mental illness in my family and among my friends and I have personal knowledge of what it can mean. But I have been forced to understand that mouthing euphemisms and talking of rights is worse than useless.

It’s based on an unwillingness to face reality and creates false expectations and false obligations. It’s crazy, really.

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