Massachusetts AIr National Guardsman Jack Teixeira, accused of classified document leak. CREDIT: Simon Ateba, TwitterThe big story Thursday was the arrest of 21-year-old Jack Teixeira, a member of the Massachusetts Air National Guard who allegedly leaked more than 100 pages of classified documents that exposed extremely sensitive information from the Pentagon regarding Ukraine, Russia, China, Israel, and documents produced by the Central Intelligence Agency and the National Security Agency.That story changed markedly through the day, though, and the sparse information we have about Teixeira raised major questions about how he could have possibly had access to such a wide-ranging tranche...