It’s part of the black American culture not “American” culture. It is also cultural to have children out of wedlock (last stats I saw were 73% in the black community - Source: http://www.cdc.gov/nchs/fastats/unmarry.htm). that is so out of step with the rest of America that is has to be cultural to blacks. If it isn’t cultural then what is it?
It is rebellion. Rebellion against acting like Americans. Black do not see Americans they see white, black, mexican etc... They will never get over the slavery issue as long as race baiters and entitlements are in place. I have a news flash for them in the history of the world there have been more non-black slaves than black. Besides you want to blame someone blame the black that actually kidnapped and sold their own people.
This all came about trying to act different than “whitey” so as not to look like they celebrate Americanism. They (and I am not meaning absolutism here) celebrate the opposite.