I have lived in some of the poorest areas in Brazil, United States, Colombia, and Mexico. I have also lived in Moldova, and some really shitty parts of south St. Petersburg in Russia, and Kyiv.
I have noticed a very very very strong correlation of how dangerous it can be just to walk outside alone, or at night, or walk in public with your cellphone. I believe there is a link between violence and race and culture.
I am sorry to ask but I have the feeling that something is missing in your comment. You said you have lived in poor areas and observed violence, or did you mean that you witnessed violence only in a subset of the areas you listed?
I have experienced violent muggings myself, witnessed violence/assaults, sometimes even without reason or purpose, in Brazil, specifically Rio/Sao Paolo, Oakland/South Berkeley(during the early/mid 2000s before the tech hit), Bogota, and Medellin. I lived years in Mexico(CDMX/tlalnapantla) and experienced all but the most opportunist crimes, like pickpockets, and nonviolent crimes.
Contrast that with living in a very poor neighborhood in Chisinau, in Moldova. Iasi, in Romania, Kiev, and Saint petersburg. I never really felt in danger at all, I could walk home at whatever hour, go on a walk, take out my cellphone. The closest to being dangerous was desperate drug addicts in St. Petersburg.
These places/slums in eastern europe are just as poor, have the same problems with the same drugs. But the level of random violence in 'diverse' places just doesn't exist. I know it sounds fucked up like I am a fox news anchor, or something, but it is just something I have noticed.
It seems the more monoculture a society is the more safe it is in the poor areas. Specifically Europe, Asia, and the middle east. I don't know how to explain it without sounding like a racist so I wont.
I have noticed a very very very strong correlation of how dangerous it can be just to walk outside alone, or at night, or walk in public with your cellphone. I believe there is a link between violence and race and culture.