Here's a wild idea. Imagine: you quite fancy a holiday, so you go to a place on your high street called (why not?) a travel agency. In the travel agency, a friendly person called a travel agent asks you what kind of holiday it is you want, and you tell her. Using her experience and expert knowledge, she shows you a few alternatives and together, you choose one.

What happens next is even wilder: she books it all. And a few days later, once you have paid the travel agency (maybe with a piece of paper called a cheque, part of a chequebook containing a handy, manually operated, readily updatable record of exactly how much you've spent) an envelope arrives at your home, holding some pieces of pre-printed card called tickets.

Sound enticing? It means, of course, you wouldn't have to spend an untold number of evenings on the internet, ploughing through contradictory and often unpleasant reviews until you've found the place you're confident (-ish) is right for you. You wouldn't, that feat accomplished, then learn from an airline website that a whole lot of other people have had much the same idea, and as a result the flights are now three times the price they were when you first looked. And you wouldn't have to print your own boarding pass (and be charged for the pleasure).

More and more, it seems, we're doing things for ourselves that once we didn't have to. Once, people were there to help us do these things: experts and professionals. The responsibility, basically, was not ours. So where, six months ago, half-a-dozen generally amiable and competent cashiers sat at the back of the local branch of my bank, there now stands a forbidding array of matt-black machines and a lone, fraught and often unamiable lady in a twin-set attempting to explain to 32 confused customers how to operate them.

At the risk of sounding like an old codger, there's more, much more: at the supermarket, we are now expected to pass our own shopping through an automated checkout machine (which invariably either fails to read the barcode, or accuses us of placing unrecognised – and thus, obviously, unpaid-for – items in our bag). We print our own maps, provide our own bags, assess our own taxes, publish our own books, print our own pictures, market and sell our unwanted goods and chattels en masse, online, ourselves. We're increasingly expected to "do our homework" about everything.

This causes problems for some, often older people. "Things aren't as simple as they once seemed to be," says Joan Bakewell. "The phone book doesn't exist any more. Older people get terribly frustrated by things like menus on phones, with endless options. Although it's hard to generalise, because older people are so often thrown back on their own resources anyway. And in many cases, we grew up doing everything for ourselves."

But it's not only adults who are expected to do things for themselves. Once, it was down to local education authorities and headteachers to decide which teachers were right for which schools. Now, according to one teachers' union, children as young as 11 are routinely required to sit in on staff job interviews, helping to select teachers – and rejecting them on the grounds, apparently, of whether or not they are prepared to sing their favourite song or, in one instance, because they "looked like Humpty Dumpty".

Some of the new things we're asked to do are, of course, good: sorting your rubbish and recycling, for example; the whole gamut of eco-activities from changing your lightbulbs to composting and growing your own. "I'm positive about all that, obviously I am," says one colleague. "But there's no denying it takes time, and energy. It does feel as if the responsibility is steadily shifting on to the individual. An awful lot seems to be up to us now."

And in a life that seems to have become increasingly do-it-yourself, David Cameron now wants us to embrace DIY government. If the Conservatives win the election, we the people are to be given the powers to run schools, sack MPs, call for local referendums on issues of local importance, and elect police chiefs. "We're all in this together," Cameron said during the launch of his party's manifesto on Tuesday. "Join us in forming the next government of Britain."

(He went a bit further than that, actually, invoking a certain US president by urging voters: "Ask not what your country can do for you – ask what you can do for your country. And yes, for your family and for your community, too." How, he asked, "will we raise responsible children unless every adult plays their part? How will we revitalise communities unless people stop asking 'Who will fix this?' and start asking 'What can I do?' Britain will change for the better when we all elect . . . to take responsibility – if we all come together.")

The idea, then, is that we do more of what has previously been considered the government's work ourselves. "Little platoons of civil society", in the Tory leader's words, will be expected to start new schools, take over the running of parks and libraries, operate local health services. Local people will have a "right to bid" to run any community service instead of the state, and a "right to buy" to protect pubs or post offices threatened with closure.

We'll be able to take planning decisions, check wasteful spending online, hold our elected representatives to account and appoint chief constables. Patients could be given control over their individual health and social care budgets. "You want to be your own boss, and you can with us," said Andrew Lansley, the shadow health minister. (Raising, as the Guardian's sketch writer Simon Hoggart suggested, the alarming spectre of DIY operations.)

But to what extent is DIY government a genuine political vision, a real means of empowering individuals and local communities – and to what extent is it simply adopting an existing consumer trend, a fairly crude attempt to save money while kidding us that we're actually in charge? How much, in fact, is it actually about passing the buck?

"The trend towards doing more and more yourself is definitely real," says philosopher Julian Baggini. "But in most cases it's down to advances in technology. The effect has been that the gap between what you can do and what a professional can do has shrunk. Actually, though, what it has done is raise the level of mediocrity, while leading us into more mediocrity."

What Baggini means, I think, is that we've been empowered to do more things a little bit better than we once could – and that suddenly makes experts and professionals look very expensive, so we do more and more ourselves, and they do less and less, so the overall quality level inexorably falls. "Digital cameras are the perfect example," he says. "They enable us to do something much better than we once could – but we're still not there. We still can't take pictures like professional photographers." We just think we can, so we do.

And applied to government, that could be dangerous. "DIY is all a big con, really," Baggini says. "All the things we say we can now do for ourselves rely on tools that have been created by other people. I've put together an awful lot of furniture, but I've never actually built any." While DIY as a political philosophy isn't really comparable to DIY as a consumer phenomenon, it's possible that because all this has happened in the technological arena, it has created a climate in which people believe they can do things as well as professionals.

"The trend to DIY has corroded the idea that we need professionals," says Baggini. "And in that context, if politicians come along and offer us DIY in, for example, local government, it could seem appealing. But maybe we should be a little bit wary of being told we can run a school. There are some quite dangerous illusions."

Social forecaster James Harkin is equally forceful. "DIY is just one of many trends in society," he says, "There are plenty of others – more and more people are outsourcing the tasks they have to do, for example: getting people to walk their dogs, or clean their ovens. But DIY in this context is a very narrow, consumer-focused notion, often based around the internet. It's about playing around, usually online, with something that's already there."

And extended to politics, Harkin believes, it's not truly empowering. "I'm sympathetic towards any attempt to re-empower local communities, really I am," he says. "That objective in the Conservative manifesto does appeal to me. But this isn't about that. You have to give local communities a reason to exist that is about more than saying: 'Hey, you could do this yourselves.' That's not empowering people, it's passing the buck. The bottom line is, we can't co-create a local dentist or a GP. We can't DIY that."

If, of course, we had the time, or the inclination. How many of us have the energy – or even the desire – to get involved in running a school or a hospital or a police force? A recent Mori poll found, in fact, that only 47% of Britons actually want "to get involved in decisions affecting their local area". We're way too busy booking our own holidays, checking out our own library books, printing out our own photos and giving our opinion of our local council's street-cleaning programme on a handy four-page form.

Still, it's good to see some entering into the spirit. Guardian readers on The Alternative Vote blog were yesterday proposing "setting up a school in my shed", and volunteering "as fireman for my street, because I have a hosepipe". Jeremy Hardy yesterday reported having successfully removed his own appendix, and Armando Iannucci led a band of 1,000 on Twitter in an inspired attempt to organise a police force for Wigan: a #twitterforce, slogan "Yes Wi-gan". Maybe there's hope for DIY government yet.