You simply did not live in a bad neighborhood by American standards. The worst neighborhoods in Chicago have murder rates far worse than Brazil as a country. For example Brazil has an intentional homicide rate around 30, whereas Chicago has 26 neighborhoods higher, with the most dangerous one, Engelwood, topping out at 172. To put that in context, the world's most dangerous city is Caracas at 120.
http://www.chicagonow.com/getting-real/2017/07/chicagos-safe...