There is short term and long term crime prevention. Long term, you are absolutely, 100% right about how to decrease crime. In the short term though, it would be

There is short term and long term crime prevention. Long term, you are absolutely, 100% right about how to decrease crime. In the short term though, it would be nice if my friends bikes would stop getting stolen and if aggressive drunk people on the local train couldn’t steal someone’s hat and then ask everyone on board “you gonna do something about it?” (neither are gang issues, I wanted to choose non-extreme but real examples). Ideally we could spend 100% on the long term but that is impractical.