Grundy, Virginia. At Appalachian Law School, a disgruntled student on the verge of his second suspension entered a school building and shot and killed the dean and a professor. He then shot four students, killing one. Hearing the shots fired, two students, Michael Gross and Tracy Bridges, ran to their cars to retrieve their guns. With guns aimed at the shooter, Bridges ordered him to drop his weapon. When the shooter turned and saw Bridges' gun, he laid down his weapon and put his hands in the air. (My pro-Second Amendment documentary, "Michael and Me," goes into detail about this incident, as well as others.)

Professor and economist John Lott checked 280 separate news stories in the week after the Appalachian Law School shooting, and only found four that mentioned the students who stopped the shooter had guns. The Washington Post, for example, said the students "helped subdue" the killer. Newsday wrote the shooter was "restrained by students." The Richmond (Va.) Times-Dispatch, however, wrote that the shooter "was wrestled to the ground by fellow students, one of whom aimed his own revolver at [the killer]." Four months later, the Times-Dispatch detailed the students' actions, including the second student's use of a gun.

What do felons think about an armed citizenry? A survey of convicted felons by the National Institute of Justice found 74 percent of the felons agreed that, "One reason burglars avoid houses when people are home is that they fear being shot during the crime." The survey also asked these felons whether they had abandoned at least one crime because they feared the intended victim might be armed. Thirty-nine percent said they abandoned at least one crime; 8 percent had abandoned such a crime "many" times; 34 percent admitted being "scared off, shot at, wounded, or captured by an armed victim"; and nearly 70 percent knew a "colleague" who had abandoned a crime, been scared off, been shot at, wounded or captured by a victim packing heat.

A survey of 23,113 police chiefs and sheriffs across the country found that 62 percent of these top cops agreed that "a national concealed handgun permit would reduce rates of violent crime." About 80 percent of rank-and-file police officers, according to polls, support the right of trained citizens to carry concealed weapons.

Israel gets it. Since the 1970s, on school campuses in Israel, policy requires teachers and parent aides to arm themselves with semi-automatic weapons. The result? School shootings have plummeted to zero.

As for Cleveland, would allowing authority figures to arm themselves have resulted in reduced casualties, or perhaps even deterred the shooter in the first place? No one can say for sure. But no doubt at least some Cleveland parents now believe the benefits of armed campus adults outweigh the costs.