Columbine was instigated and enabled by great thinkers such as yourself.
Let's not forget all the lives that could have been saved if any of the teachers or other adults at that high school had been legally allowed to be armed. They could have stopped the rampage early,merely by shooting the bad guys at the start. Or even have prevented it from happening at all because the two murderers would have known there would have been armed people there who could have stopped them. Did you notice they didn't start their killing spree at a gun club or a police station? They didn't because they wanted a easy target where there was nobody in a position to fight back or stop them.
As for guns not stopping crime,when was the last time you heard of a uniformed cop being mugged or raped?