In 1999, when two troubled teenagers went on a rampage killing 12 students and teachers at Columbine High School, national pandemonium ensued.
High schools went into lockdown, every scribbled note left in a locker was scrutinized and, say civil libertarians, there was a chilling effect on personal freedoms.
After another loner, Seung-Hui Cho, slaughtered 32 people at Virginia Tech this week, educators warned that the post-Columbine effect might forever change the freedom of intellectual thought that has been the hallmark of America's open campuses.
"There tends to be a reactive feeding frenzy, and there is nothing as horrible as what went on at Virginia Tech," said David Osher, managing director of the Washington, D.C.-based American Institutes for Research.
"There are things that can be preventative without moving into the type of overreaction that we saw post-Columbine and post-9/11," he said. "Everyone in a trench coat is not out to shoot people."
"If we try to treat our college campuses like we treat our airports, it's not going to be a solution," he said.
As the tragedy at Virginia Tech unfolds, authorities have learned the killer left a trail of clues: a monosyllabic relationship with his roommates, allegations of stalking, macabre writings and talk of suicide.
The Centers for Disease Control and Prevention says that school shootings are still not commonplace. School shootings only make up 1 percent of the total number of youth homicides in the United States, according to the CDC's Web site, and "schools remain a very safe place for children to spend their days."
Wendy Roth, who co-wrote "Rampage: The Social Roots of School Shootings," said the post-Columbine effect had been ubiquitous.
"One of the things we saw in schools was increasing zero tolerance with very little judgment allowed," said Roth, a sociology professor at the University of British Columbia Canada. "Any student suspected to be a threat was suspended or expelled."
"I hope this does not occur at the university level," Roth said. "There has been enough backlash against Big Brother aspects after 9/11 and universities know restrictiveness is not the way to go."
What Roth recommends is a system that encourages students to report "disturbing" incidents among their peers. "Stories that are part of an English paper or comments made need to be dispersed in one place."
But, Roth said, information should be in the hands of guidance counselors who have the expertise to interpret such information. Such practices are largely absent in high school and colleges, she said.
At Columbia University's Graduate School of Journalism, professor LynNell Hancock sometimes feels ill-equipped to deal with students who are showing signs of depression.
"We could certainly use some training in how to recognize depression and when to refer students and when not to," said Hancock, who teaches classes in youth issues and education. "I have been flummoxed in the past over my lack of training when I have seen students with severe depression."
But Hancock also worries that in the panic following the Virginia Tech incident, teachers may misinterpret creative student expression.
"There is a real distinct line between psychosis and creativity, and hopefully we recognize that," said Hancock.
When college students are referred to counseling, strict confidentiality laws apply, according to Sylvia Shortt, assistant director of counseling at the University of West Georgia. Privileged conversations can only be broken when students show a danger to themselves or others.
"Openness and freedom are part of the strength of campuses and I wouldn't want to see that changed," she said.
Boarding schools, which operate like small colleges with children living far from home, have used a two-pronged approach when balancing the psychological needs of their students with safety.
On Sept. 11, 2001, the planes hit the World Trade Center only 50 miles away from Peddie School in Hightstown, N.J. In the national fear that followed, the school installed loudspeakers, fences and electronic identification cards, and hired additional security officers.
When one student left a threatening note on his MySpace profile, the school took swift action and expelled him. Another student loaned his dorm entry ID to a friend, and he, too was dismissed.
"We couldn't take any chances," said school head John Green. "You find yourself on the defensive and do the safe things. You run a little scared."
After the Virginia Tech attack, Green announced a revised communication system. When chapel bells ring, students were told to gather in the campus center; when they hear the loudspeaker, "find the nearest shelter and lock yourself in, and we'll get in touch with you."
Peddie is now considering text messaging, pop-up messages and other electronic ways to communicate with parents and students on a moment's notice.
But colleges have less control over their students, who are older than 18 and adults, said Rae Goldsmith, vice president of communication for the Council for Advancement and Support of Education.
"Communications mechanisms are difficult because students have multiple e-mail addresses and cell phones, and don't always provide emergency contact information," she said.
Since the Virginia Tech shootings, college officials are not only revisiting their emergency communications plans but finding better ways to help students and faculty deal with stress.
"But you cannot force people to engage," said Goldsmith.
Education and security expert Osher said colleges should use a public health model when addressing security issues. Treat the emotional, and social aspects of learning and security will follow.
The smaller colleges have successfully created freshman bonding trips and offer smaller classes, introducing students to each other and reinforcing a sense of community, all efforts that can go a long way to not only reinforce learning, but make campuses safe.
"With a large university like Virginia Tech, community building is really important and trying to create a situation where you don't have a lonely young man," Osher said.
"You need early warning time and response, not just posting a list and going at everyone and undermining their civil liberties," Osher said. "People need to trust in a system, otherwise they don't see it as rational and they won't participate."