This past weekend I had an argument about Detroit with a guy who is a total asshole but whom it is in my personal interests to keep trying to find ways to like. I suggested the main problem with Detroit is that it is really, really, REALLY easy to move drugs there given the inability of the police to actually monitor the area effectively, and so no opportunities available to (many) people living in the city come anywhere close to the amount of money they can make by dealing.
He did not like it when I started talking about who was actually buying those drugs.
tl;dr it's mostly good news, because minimum sentences for minor drug offenses are terrible. But the downside is that any instance of the DoJ granting itself more power to decide who it does and doesn't threaten with what DOES have the potential for abuse.
That's a fair point but the DoJ already had that authority, for better or worse. Obviously it would be better for this to happen legislatively, but even if support for the War on Drugs is flagging I'm not sure I take that to mean voters oppose criminalization outright.