If someone just made the general argument that the "war on drugs" has been used immorally to and disproportionately to attack and lock up peaceful minorities, then absolutely. As long as there is racism in a society there will always be unfair application of laws, particularly laws that outlaw nonviolent acts. So no doubt there.
Only thing i call BS on is the specific content of this post and the quote provided. The content of the quote is factually and logically wrong and clearly not a truthful interpretation of the genesis of drug laws.