Forget, for a minute, that he’s the Prime Minister. Set his job aside. Let’s imagine instead that he’s G. Brown, an ordinary, partially sighted bloke a bit down on his luck who makes a mess of filling in one of his benefit forms.

Because his eyesight is so bad — left eye gone altogether, right eye compromised with a damaged retina — our Mr Brown writes with a huge fat black felt pen. It’s the only way he can see the lines. But because the pen is so thick, what he writes becomes indecipherable. He should seek help, of course he should. But he’s a proud bloke; a bit stubborn; not easy; and he wants to do the job himself.

So he inadvertently invalidates the form. Nobody listens to his stammering, hesitant explanations. He’s about to be made homeless when someone takes up his cause. The scandal makes the news: partially sighted man punished for spelling mistake, scream the headlines. Disabled man “bullied” by council officials, declare the websites.

The public are appalled. Neighbours appear on TV. “I can’t believe in this day and age that anyone could treat a blind man like this,” they say. “It just shouldn’t happen.”

The Equality and Human Rights Commission arrive with blue lights flashing and sirens blaring. Why, if the partially sighted can sue the Open University for producing inaccessible material, and Sony for selling unplayable games, then this constitutes a grave emergency.

They launch an investigation to root out the ignorant individuals who have discriminated so heinously against Mr Brown. Charges are considered under the Disability Discrimination Act. Officials are forced into grovelling public apologies; the head of the local council is removed.

It is impossibly ironic, isn’t it? That while such callous treatment of an ordinary person would create outrage, Gordon Brown the Prime Minister — a co-founder of modern, inclusive Britain, one that aims to treat all disabilities, faiths, sexual inclinations and skin colours alike — is under fire for the sin of not being able to see properly.

A disabled man, in other words, being humiliated for his handicap. Nice. Really nice.

“Fairer Britain”, it says on the Equality and Human Rights Commission Council website, in the kind of worthy mission statement that sets one’s teeth on edge but is important nevertheless. “Our overall objective is bringing people together. We focus on the need, for all who live in Britain, to have a deeper sense of commitment and mutual respect based on shared values with fairness at their core.”

Idealistic words, yes. Unwelcome, no. We live in an age that aspires to these kind of values and feels the need to define them in words. We bring up children by this public creed and hope that it spreads to their home life. There is a whole industry devoted to teaching the next generation that bullying of any kind is unacceptable; that no one should be targeted for having a physical disability or a learning difficulty; that kindness in all walks of life is officially A Good Thing.

Shame, then, that those same young people will see the treatment being meted out to their PM, a man they are taught to respect. Fair? It’s so far from fair that it takes one’s breath away. Whatever one thinks of Mr Brown he is still the PM, and whatever his considerable failings as a politician, there is something pretty vile about the personal attacks now being levelled at him.

As one partially sighted writer put it, perhaps instead of criticising we should be deeply impressed that someone who can only read large print and needs help from aides should write by hand to the bereaved relatives of soldiers killed in action. His letter was self-evidently physically laborious and came from the heart, which makes it even more sad that it is being misinterpreted.

We know enough about this man, this accident-prone politician with the sometimes dodgy moral compass, to know that he is deeply human about loss; and feels the death of every soldier as a heavy burden. In those circumstances, how cruel the misunderstanding that in seeking to go the extra mile to demonstrate his respect, Mr Brown should be pilloried for the exact opposite. What other CEO is expected to write personal condolence letters as well as run the company? Would we really prefer that he was slick and glib on such matters?

I think not. But in a way, it is all too late. The personal nastiness has become blood sport and there can only be one end. He is attacked for failing to bow at the Cenotaph (he is said to have become disorientated — the eyesight again); for the bags under his eyes; and for looking less than confident when jogging (as 58-year-old men tend to do when they can’t see properly). Mr Brown has never sought to capitalise on his visual disability and, by God, is he being punished for it.

What’s happening, in reality, is the public bullying of a man who does not deserve it. Because no one deserves it. The foam-flecked nonsense on the internet aside, the majority of the public do not like unfairness, nor cruelty, nor to watch the wings being pulled off flies. And that, from where I’m sitting, is what it feels like.

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