THE adage that “there’s no such thing as a free lunch” is being cheerily ignored by all the parties at the moment, even if what the Lib Dems are offering isn’t tax breaks of wild spending, but the chance to have the last three years, and a democratic vote, discounted. But one of the most eye-catching, and for many people, probably the most appealing, is Labour’s announcement of free broadband for everyone.

The fact that this is a brazen bribe doesn’t, in itself, mean it’s a bad idea. The digital world has a lot of things which are apparently free – search engines, social media, YouTube, streaming services, wifi in shops and city centres – though some people are belatedly coming to the realisation that if they’re not paying for the product (as with, say, Facebook) they are the product, in the form of their data and value as an audience for advertising.

Ten years ago, the then editor-in-chief of Wired, Chris Anderson, wrote a book called Free: The Future of a Radical Price (Random House, and, oddly enough, £12.99) in which he delved into the finance models of the tech industry. He cited the famous dictum that “information wants to be free”, pointing out that it was only part of a declaration, by Stewart Brand, that: “On the one hand, information wants to be expensive, because it’s so valuable… on the other hand, information wants to be free, because the cost of getting it out is getting lower and lower all the time.”

I suspect that confusion about this rather clouds the pros and cons of Labour’s policy. It is not, like their fantastically expensive and ambitious plans to nationalise rail, utilities, banks, private schools and anything else they can think of, an obviously ideological notion. There’s no reason to suppose that nationalising those things will automatically improve them, and plenty of reason to think they’ll cost enormous amounts of taxpayers’ money – the lower estimates are over £200 billion – as well as bankrupting shareholders and pension funds.

The argument that free broadband would increase productivity, provide a useful universal public service and cost a relatively modest £20 billion, though, looks superficially attractive. If it weren’t for Labour’s other spending plans, it might look like an affordable, even sensible, policy, as well as one that’s bound to be popular.

But only, I’m afraid, at first sight. There are so many questions that Labour has not answered that it raises the suspicion that it hasn’t thought about them, in its haste to produce a policy that everyone just thinks of as “free stuff”.

The first point is that getting fibre optic cable to everyone is a massive undertaking and one of the things that has made it slower is that it is not competitive enough; it’s largely done by BT OpenReach, which Labour would nationalise. There are three problems with this; the first is the stated cost of £20 billion, which must, since OpenReach has 32,000 employees (mostly well-paid and with pensions that would need covering), be a serious underestimate. The second is that OpenReach is just one bit of BT, and manages only the local loop, not the core network. The third is that the technology may be outdated (by 5G and other things) before it can be supplied.

The next issue is that although OpenReach is the biggest player, it’s far from the only one, and Labour’s claim that it will “reach agreement” with the likes of Virgin (which owns much of its own network), or nationalise them too, seems blithely casual. In any case, the cost of broadband for the individual isn’t getting the cable, it’s paying an Internet Service Provider.

The infrastructure of telecoms is not really a natural monopoly, though it may look like it; it’s a mechanism for allowing lots of different providers access to local loops, and the competition (and pricing) benefits consumers. Anyone who remembers the provision of telephones under the GPO will be sceptical about the idea that the service would be better without that competition.

Some of us, watching Iran shut down the internet in the face of protests the other day, may also be cagey about the benefits of a state-owned and controlled telecoms system for reasons that have nothing to do with the economics.

Digital access may now be more or less essential to daily life, but so are water, power, food and heating, and it’s hard to see why broadband should be free when they aren’t. What’s more, Labour have misunderstood what’s being supplied, and how; unless they also plan to nationalise Sky, Carphone Warehouse, O2 and the like, the stated objective isn’t going to be delivered.

And if the costs look like a serious underestimate, the notion that it will all be funded by new taxes on big tech companies seems equally fanciful, given every government around the world has a track record of not managing to get them to pay much so far.

It’s one of those ideas, like the jokey internet suggestion at the last election that Labour would give everyone a free owl, which sounds absolutely wonderful. Until you ask how on earth it could ever work.