Should I change my name? Wear high heels and mascara? Doctor my birth certificate? These are the inescapable conclusions to be made of Tuesday’s cabinet reshuffle in the United Kingdom, which has been reported as a concerted attack on a single social group for which it is hard to think of a precedent. The culling of white middle-aged men from the UK government was called a clear-out of the “male, pale and stale”.

Some able women have been promoted to the top table of British politics and not before time. However, the blood-letting needed to achieve that objective has had a savagery rarely seen at Westminster. Zap! What was that? That was Michael Gove being defenestrated from the Department of Education. Pow! Another one bites the dust! Biff! There goes poor Owen Paterson, the Environment Secretary, cut off in his prime, like a badger with tuberculosis. Not to mention Sir George Young, David Jones, David Willetts, Alan Duncan and Damian Green.

And let us not forget William Hague, who quit as Foreign Secretary — but did he jump before he was pushed? I hold no brief for Gove or Hague or Paterson or any of the other victims of this crude political wipeout, which targeted ministers who had the misfortune to be the wrong sex at the wrong time of their lives. Most of them had their chance and did not exactly set the Thames on fire. But as a 58-year-old (apologies for that), white (I blame my parents), male (nature played a cruel trick on me), I must protest against the muddled, prejudiced thinking that seems to have affected the British prime minister’s brain.

David Cameron has taken flak, and rightly, for appearing to surround himself with Old Etonians. Now he has lurched to the other extreme, like a drunk zig-zagging between lamp-posts, and brought in so many new female faces that the Cabinet table looks a PR photo-shoot — which, of course, it is, with a general election looming. Politics is a difficult art that very few have mastered. There have been some successful male politicians and some successful female politicians, but to favour males over females, or vice versa, is ideology gone mad.

All that should matter to a PM shuffling his pack is merit, merit and merit. Middle-aged white males have no illusions about being at the cutting edge of fashion. Most of us spend too long in the pub, let ourselves go, become repetitive in our views. But most of us are also upright citizens, pay our taxes, support our local communities. We do not deserve to be marginalised — or given this slap in the collective face. We feel beleaguered enough as it is, the victims of prejudices that can be quite as toxic as the prejudices from which women suffer. If a middle-aged man produces a novel, it is far less likely to find a publisher than the same novel written by a woman of 30.

There is a kind of casual sexism in play that does not get called sexism because the word has been hijacked. That goes for ageism, too. One great irony of the times is that people live and work longer, remain intellectually curious into their 70s and 80s — but are led by politicians who get steadily younger. As a society, Britain has never had so much experience in its ranks, or been blessed with so many people who have lived so long or done so much, from defeating Hitler to inventing the worldwide web. But do they value that experience as much as they should? Messrs Cameron, Ed Miliband and Nick Clegg are still in their 40s and, to be frank, it shows. There is a jejune-ness about their politics, an impetuousness, a reluctance to listen to wiser counsels, which has left voters distinctly underwhelmed.

Winston Churchill was 66 when he entered Downing Street. Nowadays, he would be on the discard pile, passed over in favour of someone younger and more photogenic. To be cavalier about human resources is as criminal as being cavalier about energy resources. In promoting more women, Cameron has certainly sent a strong signal and, other things being equal, the right kind of signal. The trouble is, with its crudely anti-male subtext, he has simultaneously sent the wrong kind of signal.

There will be men of my generation, still in their prime, still with a lot to give, who will be feeling a little less valued this morning. They hoped they were living in the land of fair play, where people were promoted on performance, not on their looks, and that to demote anyone on grounds of sex or age was an affront to the values of the tribe. Now they are not so sure.

— The Telegraph Group Limited, London, 2014