This bombing at the Boston martathon finish line is awful.
And we can add to this CNN list from 2011:
What is it about mid-April and violence in America?
(CNN) -- Mid-April marks the anniversaries of several horrendous attacks in recent U.S. history:
-- April 19, 1993: the FBI's siege of the Waco compound leaves 76 dead.
-- April 19, 1995: the bombing of a federal building in Oklahoma City kills 168 people.
-- April 20, 1999: A mass shooting at Columbine High School leaves 15 dead.
-- April 16, 2007: The Virginia Tech massacre kills 33.
The Oklahoma City bombing was timed to coincide with the Waco anniversary. And it's unclear whether the Columbine shooters timed that attack to mark Adolf Hitler's birthday or possibly Waco.
Is there something about this time of the year that makes these types of attacks more prevalent?
Va Tech stood alone, until today.