The debate about restoring affordability to our cities is often rancorous and out of date. Often we see the problem framed simply as a matter of regulating landlords or punishing developer greed. Renters' rights, subsidies for the poor, price controls and the like can play a role in buffering the poor from the market. All, though, have also shown themselves to be seriously inadequate given the scale of the gulf between available housing and demand for homes. Public housing can't keep pace. Nor do schemes aimed at keeping people from moving to cities succeed, even when they're repressive and unjust. Indeed, we know the approaches that won't work: all of them, other than building a lot more housing.

To make housing affordable again, we need to catch up to decades-worth of unmet demand, over the next few years. In many cities, this means goals measured in the tens of thousands of new homes; in the fastest-growing cities, it means hundreds of thousands. Build enough housing and (economists and experience both tell us) prices should at least stabilise. Want social justice? Build a lot more housing.