Philosophers have long distinguished various interpretations of the principle of equal opportunity and argued over their implications and justifications. But they have almost always tacitly assumed that the context was a national one. They have not, in particular, considered whether some interpretation of the principle could apply and be justified globally, that is, to all people without regard to their nationality or citizenship. Yet, such an investigation is clearly demanded. The leading moral theories seem to support a case for at least some interpretation of the equal opportunity principle, and it is not obvious that they can support it only domestically.
Consider, first, those moral theories which place great value on negative liberty, for example, libertarianism. Libertarianism supports a standard interpretation of the equal opportunity principle – “formal” equality of opportunity; formal equality of opportunity requires that legal restrictions j on the taking of opportunities be lifted, and such restrictions diminish negative liberty. But libertarianism would also seem to support a global. version of formal equality of opportunity, for example, that laws be rescinded which require that candidates for jobs in a country be citizens of that country, or which restrict emigration or immigration. Such laws also diminish negative liberty.
Or consider those moral theories which place great value on efficiency, for example, utilitarianism. Utilitarianism probably supports formal equality of opportunity because legal restrictions on the taking of opportunity not only diminish negative liberty, but also often prevent talent and skill from going where it can best be used and thus reduce efficiency.