Friedman always seems to have a brilliantly clever spin on any given topic. For example, take the question of immigration: consistent libertarians have to oppose any state restrictions on freedom of travel. So long as you are not trespassing, no one should forcibly make you leave. Some minarchist libertarians, however, have argued that given the existing welfare system, restricting immigration is permissable. Friedman, in his value-free economic manner, answers this.

The redistributionist tendencies of modern states are an argument against free immigration, but also an argument for it. The argument against takes the level of redistribution as given and points out its effect on who migrates where and why. The other half of the argument reverses the causation by considering the effect of migration on levels of redistribution. The harder it is for people to move from one country to another, the more attractive redistributional policies are. The possibility of redistribution tends to increase inefficient migration, but the possibility of migration tends to decrease inefficient redistribution. Consider a government in a world of free migration, trying to decide whether to increase or decrease the level of welfare. Giving people money may be politically attractive, but collecting the taxes to pay for it is not. A ten percent increase in levels will attract indigents from abroad, swell the welfare rolls, and increase costs by much more than ten percent. A ten percent decrease will cause some indigents presently on welfare to migrate to countries with more generous policies, reducing costs by much more than ten percent. The existence of easy migration makes welfare state policies less attractive, with the result that levels of redistribution are likely to be lower. - David Friedman, Welfare and Immigration - the Other Half of the Argument

The direct use of force is such a poor solution to any problem, it is generally employed only by small children and large nations. - David Friedman, Machinery of Freedom