This (Tokyo nerve gas attack) was done not by people with a political ideal but by a lunatic religious group whose idea of a happy death is mass suicide

Religious people are happier.

One major thing stopping people from coming to the city was exorbitant crime and that, for the large part, has changed,

Because two people are found guilty of the same crime, they need not be sentenced to the same.

It seemed to me... that the only valid people to deal with crime were cops, and I would like to make the lead character, rather than a single person, a squad of cops.

This assumption is mostly true-most people accused of a crime are criminals-but not always. I was accused of crime by someone I never met, in a city I had never been to... It was on its way to the prosecutor. Only thanks to divine providence and an amazing lawyer was I able to deal with it.