Only lawyers and nerds get excited about debating a website's terms of service. And yet Facebook managed to turn a change in its legalese into a PR nightmare. Here's an anatomy of the debacle.

A Harvard degree seems practically required at Facebook these days; founder Mark Zuckerberg never finished his, but COO Sheryl Sandberg and top flack Elliot Schrage have theirs. Newly hired general counsel Ted Ullyot, the veteran of several legal scandals while serving in the Bush Administration, has one, too. But we…