Alex Salmond has gone too far.

It's all very well to run down the Prime Minister and the Chancellor – what else are they there for, after all? – but it's quite another matter to malign and misrepresent the immortal creations of Dudley D Watkins.

I refer of course to Lord Snooty. Because, apparently unlike the First Minister, I actually bothered to read The Beano, I noticed the salient point about the character, which is that he was the hero of the strip. What's more, despite his top hat and Eton collar, Snooty belied his name – the strapline on his first appearance declared he was the "son of a Duke but always pally – with the Beezer kids of Ash-Can Alley".

No-one would maintain that David Cameron or George Osborne should have anything like the same claim to our affections as Lord Snooty (who personally fought Hitler, as well as the Gasworks Gang), but nor do I think they deserve the sort of brainless, thinly disguised class hatred Mr Salmond seems keen to wheel out.

If, as the current orthodoxy insists, we shouldn't judge people on the basis of their backgrounds, it follows that we shouldn't complain that the Prime Minister went to Eton any more than we should hold it against Mr Salmond that he went to the University of St Andrews, alma mater of Prince William (another Etonian, as it happens).

I've known quite a few folk who went to that big school near Slough and, though on the whole they tend to have very good manners and a certain degree of assurance, they are otherwise just as mixed a bunch as any other section of the population. Some of them are nice and others aren't.

But one thing actual toffs – again, Lord Snooty is an accurate example – tend not to be is casually dismissive of those with a different background. I'm quite certain that kind of snobbery is widespread among politicians (and at Holyrood every bit as much as Westminster), but it is not, on the whole, rooted in the traditional distinctions of social class.

The dividing line now between the political classes and the general public is better summed up by the label which was attached to Mr Cameron and his circle when they first drew public attention – the Notting Hill set.

This nebulous socio-economic group (of which Ed Miliband and much of the leadership of the Labour party would also be members) is not confined to the W11 postcode in London, nor is it a class in the traditional sense. Rather, it is that these people have a shared background in media, think-tanks or academe; they are journalists, PR people, economists and policy wonks, and it is that, and not their original social background, which divorces them from the concerns and interests of the rest of us.

Not all of them are millionaires, but they are metropolitan, and the people whom they understand least are not the very poor, nor the underclass – both groups in which all politicians take at least an academic interest – but the aspirational middle classes in less glamorous professions.

Andrew Mitchell's resignation was a foregone conclusion not because he swore at the police but because he was alleged to have called them "plebs". Whether he did or not is now beside the point – though I note that many who were lambasting The Sun and the police for their repeated lies about the Hillsborough tragedy a few days before were suddenly ready to accept the same sources as gospel.

The mere allegation was powerfully toxic, because it touched upon an assumption now fixed in the public mind and that the political classes, in their secret hearts, suspect is true: that those in political power have very little understanding of the priorities of what was once called "Sierra Man". That's also why the – on the face of it, fairly silly – story about which railway compartment Mr Osborne travels in may turn out to be profoundly damaging.

Mr Cameron's identification of "the strivers" and Mr Miliband's of "the squeezed middle" is their recognition of the importance of this group – not least because they are the people who win you a majority in Parliament. Yet Mr Salmond is wrong to blame class for the party leaders' failure to understand this section of the population.

It is not their background, nor even the fact that they are both millionaires, which hinders their understanding. It is that they, like most of the political classes, including, for that matter, Mr Salmond, devote their attention to issues which most people do not care about very much.

Alternative energy, climate change, gay marriage, minimum alcohol pricing, the voting system, reform of the House of Lords - no matter which side of the argument people are on over these issues, few of us are as fascinated by them as politicians seem to be.

It is interesting that Mr Salmond's new quasi-Maoist rhetoric on class is another of those issues shared by many politicians in every party. There is much talk about the importance of social mobility and about "widening access" (ie lowering university entry requirements for poorer students). But the truth is that Britain currently has at least as much, if not more, social mobility than at almost any point in history.

The fact that there are several Etonians in the Cabinet doesn't obscure the reality that more than half the adult population belong to a different social class from the one they grew up in, nor that four out of five children who grew up in a poor household do not live in poverty as adults.

The Prime Minister talked the other day about wanting to spread privilege. The trouble is that most politicians seem to have no idea what most of us care about. We don't really mind whether the Prime Minister is Lord Snooty, one of the Bash Street Kids or even Big Eggo. We are too busy worrying about whether we can afford to fill the car up with petrol this week, and noticing that the price of the supermarket shop has gone up by about one-third.