Terrorism: The use of violence and intimidation in the pursuit of political aims.
Terrorism is exactly what this event was. People are terrified and paranoid because the public doesn't have anything at all right now to indicate who could have done this and why. I've heard the tax day reason a lot already and that could be it but the point is nobody knows for sure. Literally the only thing that we know right now is whoever did this is a sick psychopath, regardless of whatever reasoning they have.
I've heard so far that the casualty rate is 176, with 3 deaths and 17 in critical condition. I really hope that those in critical condition recover, three deaths is three too many.