Data released Tuesday by the Commerce Dept. shows that the nation’s homeownership rate slid to 67.5 percent during the fourth quarter, levels last seen when our calendars flipped over to 2001. In other words, the much-touted homeownership gains of the entire previous Bush regime are now history. Gone. It’s amply clear now that the gains of the past eight years were illusory and temporary, created through unsustainable lending practices.