Sfrandolph
Shooter
While "Indiana" itself may not offer much of a target, you can bet your sweet bippy that there are several EVENTS in Indiana that certainly CAN be targets.
Indy 500
Brickyard 400
Mini-Marathon
MotoGP
F1 - should it return
Any Notre Dame football game
NBA Playoffs game
Possibly any PU football game...depending on who they're playing
PGA event @ Crooked Stick
Super Bowl - should it return
Indy Air Show - should it run again
As far as Hoosiers being of a different mentality than east coasters / Bostonians - Probably not. People are people are people.
If you were at an event only as a spectator - say waiting for your son to cross the finish line at the Mini-Marathon, and you KNEW he was approaching his anticipated "time", would you (generic "you") really be focused on seeing if someone in the crowd was acting weird? Watching to see if someone put a backpack down and walked away?
"it can happen here" is both A) how "the government" gets you, and B) how the potential terrorists get you, too.
Call me paranoid if you want, but I don't attend these "big" events. Two reasons. One, I don't like big crowds. Two, it makes you a target.