The case for preserving brutalist architecture requires some strange contortions. Defenders of gems like London’s Robin Hood Gardens or the Orange County Government Center must claim that buildings whose charms are derived from their heft and imposing strength are at risk and in need of our protection. This may be a necessary measure, but as with having your parents declared unfit to manage their affairs, it comes with a sense of loss. There are, of course, more tangible losses. In February, after a prolonged debate, the building that was once Chicago’s Prentice Women’s Hospital was demolished to make way for…