It was that analyst of social class, Little Buttercup, who declared that "Things are seldom what they seem/ Skim milk masquerades as cream".

The sentiment, like so many of the themes of HMS Pinafore, that ruthless examination of the class system, patriotism, party politics and the incomprehensible elevation of the incompetent to positions of power and influence, remains as true as ever 134 years on.

Appearance and perception are, of course, the stock-in-trade of public relations, so it seems at first sight surprising that a government led by a former PR man (a PR man for, of all things, a television company) whose Downing Street office is staffed – in the words of the former Shadow Cabinet member David Davis – by "25-year-old PR people" should be making such a pig's ear of presentation.

The mishandling of the NHS bill, pointlessly trying and failing to sneak a fairly reasonable policy change on pensions past the public, the absurd "pasty tax" debacle, Francis Maude's idiocy in prompting panic buying of fuel, the spivvy party treasurer offering lasagne round Dave and Sam's kitchen table for £250,000 - whatever your position on the political spectrum, we can all agree none of this looks good.

Mr Davis's warning to the Prime Minister that the Government risks being stuck with the perception that they are "out of touch" may already be too late. It certainly seems to be in Scotland, where simply calling someone a Tory is sufficient to invalidate any argument he makes. Why, last week it was even said in the comments section beneath this column online (though, as a matter of record, I'm not a member of the Conservative Party, and when at university, I spoke for the Distributists, not the Tories).

It is, however, an unhealthy state of affairs when no political party can make the case for a society based on individual liberty, social responsibility and classically liberal economics – notions which many of the population, even north of the Border, happen to support. The whole point of Mr Cameron was, it was claimed, his ability to "detoxify" the Conservative Party, so that the electorate would feel it could effectively represent these priorities. Instead, the higher reaches of his government could almost be the embodiment of the killer argument that these are the "same old Tories".

The perception that this is a Cabinet of millionaires, firmly in the pocket of other millionaires, is, as Mr Davis points out, profoundly damaging. The party's natural supporters, and those whom it needs to woo, are from that section of the electorate usually described as "striving" or "aspirational". It is the group that Ed Miliband effectively describes as "the squeezed middle", since the Labour Party needs their support, too.

And it is not merely presentational. The direction of too much of Government policy reinforces the impression that it is out of touch with those voters. These are the people who would like to be in the higher tax bracket, but by dint of earning more, not because George Osborne has lowered the threshold of the basic rate. They are worried that their children can't get a job, or buy a house. They are baffled that the Government is banging on about same-sex marriage, subsidies for wind farms, the power to spy on internet traffic and minimum alcohol pricing but doing nothing for families who now need a second mortgage to buy a first-class stamp or fill the car (if they can find a filling station with any petrol left).

In a few areas – education, welfare reform, foreign policy – things are progressing in line with these voters' instincts. But in others, the Government is actually doing the opposite of what it proposed. Anyone who voted Conservative because of the party's manifesto commitments on the countryside, a referendum on the EU, the promise to reduce public spending or Mr Davis's plans to reintroduce the civil liberties which were trampled underfoot during Labour's time in office has a right to feel disappointed.

The Prime Minister may feel that he can get away with the vast gulf between the priorities and lifestyles of his Cabinet colleagues and those of ordinary middle-class voters because the public perception of the Labour leader is even worse. "Out-of-touch toff millionaire" may not be a great label, but it's better than "born loser who couldn't run a bath". But it's a dangerous thing to pin his hopes on. If the Conservatives, under Mr Cameron's "modernisation" process, can learn from Blairite techniques of spin and party management, Labour could as easily imitate the Tories' ruthlessness in getting shot of useless leaders.

It begins to look as if the Conservatives have learnt very little, either from their extinction in Scotland or from the agonising years in the wilderness at Westminster, rethinking and restructuring their "brand".

It was easy to claim that the party would handle the economy better than Gordon Brown, but – unbelievably – public spending is actually still going up. What is the point of making a huge deal about supporting the NHS and ringfencing its funding, and then making such a colossally ham-fisted job of introducing reforms in England which practically no-one can understand, but which they predictably assume will amount to privatisation? What has happened to those (rather good) plans for greatly increased localism, devolution of powers to the grassroots, encouraging voluntary groups? There is no point in yakking about the Big Society at the same time as capping tax relief on donations to charities.

One of the public's great frustrations with politicians of all parties is that they say one thing, but do another. Mr Cameron's real problem is not just that his opponents, and his potential supporters, assume he and his pals from Notting Hill are the "same old Tories"; it is also that those who did support the party's plans have noticed that his Government isn't introducing very many of them. Indeed, they think it isn't very Conservative at all. And while the Government may be hated because they look like Tories, they are certainly doomed if they don't start acting like Tories.