His launching point is ... MJ is bad, but "The moderate consumption of alcohol has a strong place in the Catholic tradition, and Catholics need to be able to distinguish this practice from the use of a drug."
Yeah, but where the moral theology about WHY moderate consumption of alcohol is OK according to Catholic PRINCIPLES, and why do these same principles not apply to MJ. Alcohol is just as likely to be abused as MJ (if you were to sell the latter in controlled doses). Apart from Catholics, who believe that it's grave sin to lose control of your faculties, 90% of the rednecks who walk out of the convenience store with a 24-case of beer are going off to get drunk and lose control of their faculties. Tons of people are killed each year by drunk drivers, lots of people become alcoholics, become violent and commit crimes, etc.