When a homeless man named James Allen Hill overdosed and died in the restroom of the San Francisco library last Friday afternoon, it was a shocker. A drug overdose in the public library? Really? "It was an unfortunate and tragic incident for everyone," said library spokeswoman Marcia Schneider. "Especially for the security staff that handled it." There will be those who will see Hill's death as a failure of the system, another example of how the city neglects its poorest residents. That's not the story here. The city did anything but neglect Hill. But his case does show a flaw,...