Of course it is - just like opposition to alcohol Prohibition was a conservative idea. Drug criminalization, like Prohibition before it, is "progressive" social engineering that has succeeded only in enriching criminals.
I state, emphatically, having been a conservative for the past 34 years, and after having read a great deal of books written by a great many conservative leaders, LEGALIZATION OF DRUGS IS NOT A CONSERVATIVE VALUE.
What did those books say about the conservatism of opposing Prohibition? About utopian social engineering such as attempting to eradicate through government force the millenia-old pursuit of altered mental states? About the law of unintended consequences, as illustrated by drug criminalization's inflating drug profits and channeling them into criminal hands?
OMG, you are so obtuse.