Well, in the '70s the Democrats were perceived as weak on drugs, the party of "acid, amnesty and abortion" circa McGovern's run in 1972. And the Supreme Court delivered on abortion in 1973's
Roe v. Wade, and Carter on amnesty for Vietnam era draft dodgers on his first day in office in 1977.
But I don't remember any president in my politically aware lifetime really being "weak" on drugs (any more than they were weak on crime, that is). And by the same token, opposition to the War On Drugs is not particularly ideological, it's a requirement for libertarians, lots of notable conservatives including William F. Buckley have opposed it ... overall it's a colossal mess.
Although I'm entirely uncertain a complete reversal would be better for anything but civil rights, especially since efforts in that direction in other First World countries have not worked well to my knowledge. And there are worrying studies that indicate marijuana might kindle schizophrenia, which we as a society no longer handle well at all.
Me, I said prior to all we've learned in the last few months that make it look like a sideshow, that we could have a free society or a war on drugs, pick one. This made no impression on parents I've discussed it with, they are terrified their kids will be harmed by them.