Not sure this is true. My rough calculations are based on: approximately 7000 murders by black people in 2014, population of 37M.
By my calculation that comes out to a rate of about 19 per 100,000.
Meanwhile, Honduras has a murder rate of 90 per 100,000.
There are 31 countries with a rate above 19, so "black America" would be #32.
Interestingly, the US Virgin Islands are #3, at 52.6.
However, it's entirely possible I bleeped up the calculation. If so, corrections appreciated.
https://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate
That is just homicides. I said black violence. Annual violence:
MURDER
White:4,382 = 1.77 per 100k.
Black:4,498 = 11.83 per 100k.
RAPE
White:10,990 = 4.45 per 100k.
Black:5,428 = 1,428 per 100k.
ROBBERY
White:41,962 = 17 per 100k.
Black:56,948 = 150 per 100k.
AGG. ASSUALT
White:208,081 = 84 per 100k.
Black:112,325 = 295 per 100k.
OVERALL VIOLENT CRIME
White:265,754 = 107 per 100k.
Black:179,636 =473 per 100k.