The world was stunned Friday by a double tragedy in Norway: An explosion in the nation's capital, Oslo, left seven dead, while a shooting spree on the nearby island of Utoya reportedly claimed the lives of 86, mainly teenagers from a Labor Party youth camp. Though many at first suspected the involvement of international terrorism, both acts of violence have now since been pegged to a 32-year-old Norwegian man named Anders Behring Breivik . Breivik has confessed to orchestrating both attacks, and says he acted alone. (Though he made further statements in a court hearing today -- where he pleaded not guilty -- that have stoked fears about two more possible terror cells in the country.) Breivik has called his actions "atrocious," but also "necessary." The facts we've learned about Breivik in the days since the massacre paint a portrait of a disturbed and isolated man. Unearthed documents have shown that Breivik -- the son of a retired Norwegian diplomat ...