Is Labour’s plan to make bus travel free for under 25s a clever political gambit, which will lock in the youth vote by helping out a group struggling with low wages, insecure work, and soaring living costs? Or is it just the latest sign that Jeremy Corbyn is intent on buying his way to Downing Street, and possibly also a communist? The policy is all of half a day old, and both those takes can already be found roaming the internet in herds.

I’m uncertain whether free bus passes in council areas that take back control of their bus networks will make for good policy: in many ways it looks great, but there are niggling doubts about practicalities. As a piece of politics, though, it looks like a masterstroke. It’s the latest incarnation of a trap the Opposition has set for the government several times now – yet the Tories seem determined to fall for it every single time.

Policy first. Making it cheaper for young people to travel is A Good Thing, which will make it easier for them to stay in education or access jobs. What’s more, buses are by far the best way of moving large numbers of people around most British cities. (London’s comprehensive rail network is, if not quite unique, then certainly very unusual.) In terms of making efficient use of scarce space, and reducing things like traffic and pollution, anything that encourages people out of cars and onto a bus has to be good.

What about the fact the policy will only apply where councils either take over bus networks themselves – or, more likely, plan and franchise them, as Transport for London does in the capital? Well, this strikes me as a good thing too. Deregulation of bus networks has been an utter failure, resulting in high fares and confusing ticketing. Most damagingly of all, it’s undermined the whole idea of local transport in many areas, by allowing private firms to cherry pick the most profitable routes while lumbering councils with expensive but socially necessary ones. After 30 years it’s so clear the policy has been a mess that even the current government has talked about rolling it back. It’s no coincidence that London, where bus travel has boomed, was never forced to deregulate itself.

On the whole, then, I think this is a pretty fine idea. The only bump in the road could be the money. Labour says it’ll cost £1.4bn a year after five years, a figure it claims is based on use of the existing bus passes among the elderly. The Tories, assuming 10 journeys a week for every young person in Britain, put it at £13bn.

It’s tempting to assume the final figure will be somewhere between those two, but in all honesty we don’t know. This policy will change both availability of, and enthusiasm for, bus travel. What that’ll do to the final cost it’s hard to say, but Labour’s guess may well be on the low side.

For that reason, I’m cynical about the party’s claim it can fund this by hypothecating a chunk of road tax – not least because, if fewer kids buy cars, then that must have some impact on how big that pot is. It’s a neat answer to the inevitable questions about how the party plans to fund this, but I’m not entirely convinced the sums will add up. (At lunchtime, for what it's worth, a Labour advisor emailed me to point out that a 2017 report from UCL found that making all buses free for everyone would only cost £5bn per year. So I think we can say the Tory estimate is a bit on the high side.)

If it only gets an eight and a half out of 10 as a policy, though, as a piece of politics, it’s worth at least 13. As with tuition fees and rental caps before it, the bus announcement has pushed the Tories into making a bunch of statements suggesting that they don’t care about young people, don’t think they’re worth spending money on, and don’t have the slightest clue about the problems that they face.

Nusrat Ghani, for example, accused the opposition of “bribing young people” (this, unlike bribing old people, is for some reason verboten). She also cited the millennial rail card, as her government’s contribution to getting transport costs down. Given that she’s a transport minister, this statement that shows a frankly incredible level of ignorance about how little use a railcard would be in most cities around the country.

All that was nothing compared to the tweet from Tory chair James Cleverly – sometimes, bafflingly, tipped as a rising star – who sent a tweet implying the policy was somehow infantilising 24-year-olds. Whether he thinks the government is infantalising old people by, say, handing out winter fuel payments is a matter on which he has yet to comment.

If it’s ever implemented, this will, I think, be a good policy, both for local transport and for young people. But that’s a long way off. In the meantime, the main beneficiaries of the policy will be the Labour party.

Because every time a Tory sneers at the idea we could ease the burden on young people, they are sending a message. “We don’t know how to solve your problems,” it says. “This party isn’t for you.”