>to talk people down instead of rile them up

Well then, police budgets would go down! And if police budgets go down then you are less safe!

Having no crime is more dangerous for politicians then some baseline of crime. If there is no crime they can't run on a hardball anti-crime platform and ignore everything else. If you run into a situation where there is no crime, it's easy enough to go invent some, generally focused at the young and poor.