The Bill, a landmark in firearms legislation, outlawed some semi-automatic "assault weapons" and required background checks on gun purchasers.
Politicians, church leaders and ordinary members of the community said that it should never be allowed to happen again. Unfortunately, it did.
Since then, the US has witnessed more appalling and seemingly motiveless mass killings, three of the worst being at Columbine High School in Colorado in April 1999, another mass killing in the middle of Atlanta three months later, and a church shooting in Fort Worth, Texas, in September.
For many Americans, including the three million members of the National Rifle Association, the right to bear arms is not only enshrined in the constitution, it is a key civil liberty.
The right was born out of the War of Independence when armed militias had the right to protect property and people.
It grew in importance as the union headed west into an environment where the only law was that of the gun and the hangman's noose.
There are an estimated 200 million privately held guns in the USA. One million weapons are in the hands of students, some of whom take the guns into high school.
More than 14,000 homicides were committed with firearms in 1996. Of the dead, 68 were children below the age of four. More than 5,500 of those killed were aged between 15 and 24.
Overall, the highest death rate per capita is for men aged between 20 and 24 at 30 per 100,000. Black males in low-income, inner-city areas, are even more likely to be shot.
In the 12 months prior to Denver there were seven fatal school shootings, which left 16 dead. Many inner-city high schools now use airport-style security gates to screen out weapons.
Many newspapers, including key opinion formers, are questioning the wisdom of widespread gun ownership.
Former President Bill Clinton and his wife Hilary have emerged as prominent supporters of tougher controls.
The law
State laws on ownership, carrying and use of firearms differ widely. There are various levels of checks depending on what kind of weapon you want.
Click here to find out about recent legislation.
Some states allow the purchase of both rifles and handguns without any form of prior licence. Others have totally banned the carrying of handguns and are moving against "concealed weapons".
State laws often mirror the demographic of the population - large rural populations have retained a more relaxed attitude towards firearms than cities.
But even before the Columbine killings, the debate had intensified - and nowhere more so than in Colorado.
The National Rifle Association campaigned for months to persuade the state legislature to pass laws allowing the carrying of concealed weapons.
Denver Mayor Wellington Webb took out full-page newspaper adverts against the measure, arguing that there had been a 42% drop in homicides since tighter laws in 1994.
His campaign - coupled with the killings - led to the proposal being hastily shelved. Despite the killings, the NRA went ahead with its annual conference in Denver, albeit in a much more toned down form.
Under the gun
Two of the major gun control successes in recent years came when gun firms agreed to manufacture child-proof locks following the accidental deaths of 200 children and then President Bill Clinton pushed the "Brady Bill" through Congress.
The Bill, a landmark in firearms legislation, outlawed some semi-automatic "assault weapons" and required background checks on gun purchasers.
Many members of his own Democratic Party then accused Mr Clinton of backing off from tougher measures after the Republicans, many of whom are backed by the NRA, gained control of Congress.
However, on 8 April 1999, anti-gun campaigners celebrated an important symbolic victory when Missouri narrowly rejected proposals to allow the carrying of concealed weapons.
The result, watched by the entire nation, came after high profile campaigning from Hilary Clinton and, on the other side, a $4m NRA offensive.
Campaigners heralded it as a step forward - but amending the constitution is not even up for discussion.