Did you forget the sarcasm tag??
These young men have rejected the Judeo/Christian culture of America for that tribal, feral culture of Africa.
That is their option.
That culture doesn't seem to frown on killing someone of a different tribe...and, in America, it certainly doesn't frown on killing Whitey.
In fact, that culture admires and honors those who attack Whitey.
I am not passing judgment on that culture...I am just describing its nature.