Patrick Ireland will forever be known as "the boy in the window" after television cameras covering the Columbine High School shootings captured the bloodied and limp 17-year-old dangling out of the library's second-story window.
It was 2:38 p.m. on April 20, 1999 -- more than three hours after Eric Harris and Dylan Klebold attacked the suburban high school with automatic weapons and explosives, killing 13 and injuring 24. Ireland had been shot in the brain and foot.
Confusion reigned as SWAT teams grabbed Ireland, then stormed the school, where 200 to 300 terrified students and staff cowered under tables, above ceiling tiles and even in a school freezer.
"We were all shot fairly early on in the library," Ireland, now 27, told ABCNews.com. "We heard shots as they got closer, throwing pipe bombs, things falling from the ceiling. It was a surreal experience.
"Within the first third of the time frame I blacked out and was unconscious through the mayhem. It was kind of a blessing in disguise," he said. "I don't have a memory."
But for most Americans on the 10th anniversary of that tragedy, those images are still seared into their collective consciousness: two bullied outcasts, clad in trench coats, seeking revenge on "jocks" and minorities.
Today many still cling to myths about how the shootings happened, what motivated the killers and how to make schools safe, as survivors have tried to make sense of their own lives.
In the decade after Columbine, the U.S. saw 80 more school shootings, even as millions of dollars have been spent on metal detectors, security cameras and emergency response plans.
"Schools implanted some programs that were effective in reducing school shootings, but others were politically expedient and popular, but ineffective," said Northeastern University mass murder expert Jack Levin, who writes about Columbine for Behavior Science magazine.
"The law and order approach instituted in schools doesn't work very well," he told ABCNews.com.
In the 1997 school shootings in West Paducah, Ky., two students pulled a fire alarm then waited until students fled the school.
"They shot them down like ducks in a gallery," said Levin.
Attempts to put more police in schools have also failed. "To this point we haven't been able to get to a crime scene and prevent mass slaughter," he said.
Resource officers were present at both Columbine and the 2008 shooting at Northern Illinois University, according to Levin. Costly preventive programs aimed at bullying and conflict resolution work better, teaching empathy, anger management and impulse control.
In 2000 a national school safety report attempted to characterize the typical school assassin, concluding that most are male loners with a grievance. More than half had revenge as a motive.
But law enforcement and educators still agree that profiling students has been ineffective in predicting which teens will become killers.
"There are a million men who are psychopaths and a few women, but they never kill anybody," Levin said. "They might sell you a bad used car or might clean out your portfolio of stocks or they might womanize or cheat. But killing's not their game."