Drugs - let's face it, the only people urging the laws to be relaxed either a) want to eliminate any risk of prosecution or public persecution for using them themselves or b) believe they are in a position to profit from higher-class drugs being given a legal route to market.
Recreational use is now so prevalent in youth culture, it's difficult to see how relaxing laws will prevent widespread, continued use on an epidemic scale for future generations.
Yes, we all know alcohol and tobacco are bad for you if they're abused, but one very rarely hears of a burglar robbing a house because he needs money for 20 B & H or a can of Skol Super.
A comprehensive education, at early high-school level, is the only way to fully address the issue. If the side-effects, for both the individual and the impact upon the society in which that individual 'lives' are emphasised, any known drug-taker within that sphere will soon be ostracised by their peers, at that age.
Ban All Drugs For Recreational Use, In Toto.