That's why the penalties for cocaine are historical less than for crack despite them being the same drug.
It's not racial per se -- in the original message I think "dominant mainstream culture" would be better than "white" -- though in the 50s and 60s those were almost the same thing. Back then the dominant culture implied white, English-speaking, and protestant Christian, and other cultures and ethnic groups were second class. That's much less true today but not totally.
I'm speaking to the historical reasons for the war on drugs, which are mostly related to racism as well as a desire to suppress subcultures like the 'hippie' movement. The original propaganda used to make marijuana illegal was all about black men seducing white women. Google it.
If the war on drugs were about health and based on rational health evidence, marijuana would be legal and alcohol would be schedule I.
Your racism is showing.
Upper class people like Cocaine too, care to inject a racial undertone as to why that is illegal?