The largest single school shooting in U.S. history, which occurred at Virginia Tech in 2007, was perpetrated by Seung-Hui Cho.

CNN: Rejection, bullying are risk factors among shooters

"The heinous crimes committed by Seung-Hui Cho were an unprecedented act of violence that no one could have foreseen, " Mr. Owczarski said.

WSJ: Virginia Tech Is Liable in Shootings

In the 2007 shootings at Virginia Tech, which resulted in the deaths of 33 people, gunman Seung-Hui Cho had been considered dangerous by a court and ordered to get outpatient treatment.

WSJ: Arizona Shooting Puts Focus on Gun Laws

During the trial, the plaintiffs argued that the two victims might have survived if school officials had issued a campuswide warning sooner about the first two victims shot by the gunman, Seung-Hui Cho.

WSJ: Virginia Tech Is Liable in Shootings

Virginia Gov. Bob McDonnell, a Republican, an advocate of gun rights, has also focused on the importance of the national database since Seung-Hui Cho killed 32 people and himself at Virginia Tech in 2007.

WSJ: Systemic Gaps Hinder Background Checks for Gun Purchases

Faculty said the school its full name is Virginia Polytechnic Institute and State University responded far more quickly Thursday than it did in 2007, when student Seung-Hui Cho killed 32 people before taking his own life in the worst campus massacre in U.S. history.

WSJ: Two Killed in Virginia Tech Shooting

Apart from the evident fact that Cho Seung-hui should have been institutionalised long before he committed his crimes, not one of your suggested changes to America's gun laws would have prevented him from obtaining high-capacity, semi-automatic handguns.

ECONOMIST: The OECD