First there are new forces in global politics. Secondly, these new forces constitute a change in the nation-state system but do not necessarily signal the end of that system. Finally, the challenge faced by the political scientist who wishes to understand the significance of these new forces and the change they affect is to discover what gives rise to new actors and trends, to define new forces in terms of themselves, so that change itself, whether in fact or in theory, may be better defined and understood.
In order to determine whether any international actor or trend is a legitimately new force, and therefore to be characterized as an agent of change, one must first, at least to some degree, define change. Scholars have developed three criteria for doing just that. The first requires that the so-called "Great Divide" between a state's domestic and international policy be compromised. Secondly, a state must lose control over the development of personal or social identity among its citizens. Finally, a state must relinquish its role as the primary player, giving way to some sort of global society which would have replaced what has been considered an international anarchy. These three points are often characterized as the structure of the nation-state system. It is up for debate whether all of these conditions must be met for change to occur or whether partial change is possible. It seems, however, that, by definition, when any element of a structure is compromised, then the entire structure itself is changed. The change may not be profound. It may not be permanent. But it is change nonetheless.
That being said, it is important to understand that there is a difference between the structure of the nation-state system and the nation-state system itself. In Waltzian terms, the structure is simply an arrangement of parts; a system, however, consists of structure and the ways in which the elements or units of that structure interact with one another.