Today’s housing market combines the worst of two worlds: a lack of supply for those with the means and desire to buy, and unaffordability for those of lower income. A June report for the National Association of Realtors found that the growth in U.S. housing stock over the past decade was less than half what it was between 1968 and 2000, “exacerbating a growing affordability crisis in many parts of the country.”

While there are many reasons, including such fundamental problems as the lumber supply, a key, long-term cause of housing shortage and its social implications (including the capacity for those of low income to accumulate wealth through property ownership) lies in our housing policy history. We once had a reliable formula for housing a wide range of income groups but have turned our backs on it.