When it comes to actual threats to society, I place drunk drivers at the top of the list. Anyone who threatens, injures, or kills indiscriminately and uncontrollably is a threat to my society.
In the US we will throw someone in jail for 5-10 years for simply possessing a piece of vegetation. They don't even have to do anything with it.
But someone who kills innocent people by driving drunk can get less. I applaud the countries with harsher drunk driving laws. In that case, they are focusing on what is truly the threat to society.
In my opinion, there is little difference between me driving drunk and killing someone and my getting drunk and going out and shooting someone one.
Bottom line: If someone can't be trusted not to get drunk and drive (especially if they kill someone), they can't be trusted to be out free in our society. The prison system is designed to keep people who are threats to our society separate from society.
But instead the threats seem to be people who use a naturally growing plant. Not that I am a huge fan of legalizing drugs, but it is time that the alcohol lobby starts getting ignored.
Perhaps the solution is to mandate a license to drink which has to be renewed against any criminal activity. Get caught driving drunk, lose your drinking license? I dunno.
Just an old souse's opinion.