In the initial section of his article, Ersun Kurtulus criticises the approach to sovereignty which I advanced in my Sovereign Statehood (1986). There I argued that the characteristic which distinguishes a sovereign from a non-sovereign state is constitutional independence—that is to say, a territorial entity's possession of a constitution which is not subordinate to that of another territorial entity. The most obvious and graphic way of identifying this distinction is to compare the position of a sovereign state with that of a territory which is part of a federal state. Thus Iceland is a sovereign state; Texas is not. It is her constitutional independence which, in international practice, is deemed to confer sovereignty on Iceland, and so make her eligible for full international actorhood. By contrast, non-sovereign territorial entities do not enjoy such actorhood, and most have none whatsoever.