When someone disrespects someone else, either verbally or physically, just because they are from another state. Usually has to deal with northern states vs. southern states, like in the Civil War. Or if the person doing the disrespecting is from Texas.
Texan: I hate Pennsylvanians. Them and their damned ketchup. (Heinz Ketchup originated from Pennsylvania)
Pennsylvanian: Don't be a statesist, dude. Hate isn't kool.
Texan: Screw you.