They already failed to prevent 600 common murders each year. You could call that completely ineffective or you could call it diminishing returns on investment in security. You can&#x27;t prevent all of them without an unacceptable number of false positives or harsh restrictions on freedom.<p>Anyone who&#x27;s upset by this and doesn&#x27;t have a personal connection to the victims is not being rational. They should be upset by all other killings - the vast majority which don&#x27;t get into the international news, let along HN. Those are far more prevalent, and perhaps easier to prevent because they&#x27;re done by amatures.