Poussaint, who is black, believes that racism — like other human behaviors — exists on a continuum, and that racism's extreme forms, in which a person has racist delusions that can lead to violence, should be considered a serious mental illness and be listed in the DSM.
The association's officials disagree:
"Brutal, violent hate crimes are usually committed by mean, not sick, individuals and groups. We must not provide the convenient excuse of mental illness for those who are not genuinely ill," APA President Daniel Borenstein wrote in the association's newsletter last September.

I'd have to say no.. it's not a mental illness. Most likely a guy who runs around killing people (based on a skin color or not) probably has other mental issues that could be diagnosed. But blind hatred of a skin color is just ignorance (which could of course be a result of another mental illness)