You say mistake as if it were an intentional choice that turned out to be a bad one. I don't know my history of this subject very well, did policymakers really sit down and encourage homes to be treated as investment, leading them to become less affordable? Or were homes becoming less affordable just the natural consequence of having an expanding population and fixed supply of land? I'd always sort of assumed the latter.

Congress made mortgage interest payments tax deductible in 1913, which gave folks an incentive to think of houses as investments.

Increasing home ownership was an express goal of the Bush Administration: https://www.youtube.com/watch?v=GkAtUq0OJ68&ab_channel=vastg...

They wanted to promote an "ownership society": https://en.wikipedia.org/wiki/Ownership_society

Great questions.

There is a good NPR Podcast about the mortgage interest deduction and how it led to many unintended consequences like inflated prices and oversize houses, high mortgage debts, etc. https://www.npr.org/sections/money/2018/05/23/613834765/most...

A consequence of low-density policy built in the days of white flight and redlining, actually.

After a few decades of nobody having the rights to control their own property, it became ingrained that this is how it should be.

As soon as we let people vote to deny their neighbours the right to build a home (or convert a house to apartments, etc.) we gave homeowners the rights of a cartel to increase the value of their asset.

Here in Australia it was definitely intentional choice, or at the very least, intentionally expanded upon.

forfend?