AFTER the financial crisis of 2008, there was one thing that almost everyone agreed on. The government-sponsored mortgage giants, Fannie Mae and Freddie Mac, had to go. While shareholders and executives reaped the profits from Fannie and Freddie in good times, taxpayers were stuck with the bill in a crisis. President Obama described their dysfunctional business model as “Heads we win, tails you lose.” But here we are, seven years after the crisis, and nothing has changed.

In the 2008 crisis, when it looked as if Fannie and Freddie might go bankrupt, Henry M. Paulson Jr., then the Treasury secretary, argued that their fall would cause economic catastrophe. Foreign investors, stuck with their securities, would panic, and the mortgage market would shut down. So Fannie and Freddie were put into something called conservatorship, and are now government controlled, supported by…