Try listing every problem the Western world has at the moment. Along with Covid, you might include slow growth, climate change, poor health, financial instability, economic inequality, and falling fertility. These longer-term trends contribute to a sense of malaise that many of us feel about our societies. They may seem loosely related, but there is one big thing that makes them all worse. That thing is a shortage of housing: too few homes being built where people want to live. And if we fix those shortages, we will help to solve many of the other, seemingly unrelated problems that we face as well.