Here's an excellent article on drug liberalisation. It's particularly well-written, but doesn't say anything particularly new and I'll assume that we all agree that drug liberalisation is the correct policy to implement with only practicallities to work out (what should be legalised, when, for whom, available where etc).
What I don't understand is why every mainstream party remains resolutely in favour of prohibition? The victims of drug use whose votes are being courted are surely those who are robbed to support drug users' habits. A politician staunchly in support of prohibition is saying to these people this:
"Drugs are a scourge on society because drug users commit crimes that hurt people like you. So to help people like you, we will continue a policy that keeps the price of drugs artificially high meaning drug users have to find more money. Furthermore we criminalise drug use itself so that users find it increasingly difficult to find legal employment, so they will increasingly resort to real property crime, committed entirely against people like you. Finally we will continue woefully inadequate public education on the real health risks of drugs - and often complete misinformation - to make sure that your kids continue to be much likely to use illegal drugs than kids in countries with liberal policies such as Portugal and the Nederlands. And despite the fact that the supply of illicit drugs has become the third largest industry on Earth (thanks largely to us artificially increasing prices through prohibition), we will resolutely abstain from applying any tax at all on it, instead surrendering the entire revenues to violent organised international criminals and increasing taxes on hardworking families like you to pay for incarceration of drug users and our futile attempts to reduce drug supply. I trust I can continue to count on your vote...."
The reason we have a 'war on drugs'(TM) is to fall in line with a decades-old American policy born out of a peculiarly American zeal for puritanical religiousity and authoritarianism. It really shouldn't resonate with educated Europeans at all. So why does it remain universally popular among political parties, and presumably a clear majority of voters as well?