A similar number of dead (thirteen thus far in Texas, thirteen not counting the shooters at Columbine). A similar number of wounded (news outlets report 31 in Texas; 24 at Columbine). An institutional setting that seemed extremely safe. Early confusion about additional conspirators (at Fort Hood, two soldiers thought to have possibly been in cahoots with suspect Major Nidal Malik Hasan -- originally said to be dead, although he's still alive at this writing -- were reported to have been taken into custody; Hasan's now being identified as the lone gunman). Warning signs that were ignored (this morning, NPR told about a Hasan lecture on the Koran a few years back that left attendees wondering if he might freak out and kill a lot of people). Suspicious Internet posts (perhaps including one by Hasan that seemed to praise Islamist suicide bombers).
Yes, these are coincidences -- but that doesn't make the emotions they spark any less profound. Ten years after Columbine, I've still been unable to make myself read a book about the shootings by Dave Cullen, an acquaintance of mine. And the first report I heard about Fort Hood instantly transported me back to that terrible time. I suspect I'm not alone.