DELPHOS — “I pledge allegiance to the Flag of the United States of America and to the Republic for which it stands, one nation…” Then there was an abrupt crackle and whine emitted from the microphone attached to the PA system. “Attention, attention, code purple, code purple. There is an intruder in the building,” Principal Miller spoke with a calm, yet rigid voice.

A silence fell across the room and the students’ eyes turned to their teacher, Mr. Smith, who immediately sprung up from his desk and went into action.