Most models about global sustainability treat the world as if it were a homogeneous, single-nation system. However, the clustering observed among nations with respect to their economic development levels results in two distinct blocks; developed (North) and developing (South). Interaction of these blocks and their local actions affect the global sustainability, as they are two interrelated actors in a closed system, namely the world. In this study, population, economic growth, welfare gap, energy supply and related pollution are identified as the key issues related to both global...