USA has the highest incarceration rate. Why?

[chapset]

MARCUSDJACKSON said:

chapset said:
I don't trust that picture post in the OP there are too many third world countries with a lower incarceration rate then first world countries when by a fact they have the highest murder rate (http://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate) and everyone no povrety is the mother of crime

they don't keep prisoners. they kill them.

that or the majority of the crimes are never even reported