Meanwhile, the party’s intention for many of these homes to be built in “new towns” suggests a lurch towards state planning that fails to take into account where people actually want to live.

While the ambition to “level up” areas outside the South East has plenty of merit, there is a danger that housebuilding becomes part of this strategy, and homes are ultimately built in areas with far less demand.

New homes have to follow the market: it’s simply not going to happen the other way around.

But despite boasting some plans that are unlikely to move the dial, it’s significant that Rayner also mentions building on “grey belt land” – pieces of the green belt that are anything but green.

It’s something Labour has talked about before: a willingness to override housing and planning rules to build homes on intensively-farmed agricultural land or abandoned car parks that somehow got classified as “green belt”.

But they didn’t need to intentionally refresh memories of the idea during an election – not least because it is one of the most controversial aspects of planning reform.

The decision to do so, again, suggests a seriousness on Labour’s part about recognising how important it is to add to the UK’s housing stock – and shows a willingness to fight on behalf of younger generations to do what’s necessary to get homes built.

And perhaps only Labour can have this fight. The party’s electoral base is not dominated by those who would prioritise, above almost anything else, seeing the value of their home surge.

Of course, if the polls are anything like correct, Labour MPs may soon be finding themselves representing some Nimby areas once deemed comfortable Tory seats. If that day comes, it will be a real test for the leadership of the party, to stick to the promises they made to get to such a position.

If they’re savvy, they won’t be thinking about the frustration with the status quo that got them into No 10; they’ll be thinking about what kind of legacy might keep them there.

The most powerful one, by far, would be to become the new party of home ownership.