In some countries it [citizenship] is, in effect, on sale. In others, such as America, it may be an accident of birth, with no conscious choice involved. Rather than making a fetish out of passports, a better approach would be to use residence (especially tax residence) as the main criterion for an individual’s rights and responsibilities. That encourages cohesion and commitment, because it stems from a conscious decision to live in a country and abide by its rules. The world is gradually moving in this direction. But many states (mostly poor and ill-run) resist the trend and some rich democracies like the Netherlands and Germany are trying to curb it (see article), offering a variety of excuses.