Erik Voeten wonders about drug tourism to Colorado and Washington state:
It could be that these states (and especially the border areas) are sufficiently sparsely populated that the nuisance of drug tourism is going to be less visible and the political power of those affected less strong than in densely populated The Netherlands. Nevertheless, the Dutch experience suggests that there are some downsides to being a first mover on this front. Policy makers in other countries have pointed to increases in petty crime and localized opposition as an argument against further legalization; thus amplifying the problems for the Netherlands. It may be that the American West harmonizes more quickly but we should think about why this has not happened in Europe.