that this will be tough. but stopping those that are known to be mentally ill and/or under treatment will go a long way. also, keeping those who commit crimes with guns in jail (please google project exile) has had excellent results. there is never going to be a perfectly safe world (just look at the slaughterhouse our roads have become), but the answer in a free society should never be to reflexively "ban" things (like silly cuomo in NY).
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