Sovereignty over the South China Sea waters and the territorial features therein has been a contentious issue since at least the 1970’s, with conflicting claims going back even further. Key concepts of Liberal and Neo-Realist International Relations Theory are used to assess respective theory’s explanatory capability for why the South China Sea Dispute is difficult to settle. The scope of the study is limited to three pairings of international relations: China-Philippines, China-Vietnam and China-USA. The analysis concerns the development of these sets of international relations from 2016 up until now. The findings point to unilateral action by one claimant in the face of contesting claims by another as being one of the main factors perpetuating the conflict. Treaties and international law are designed with Liberal development of international relations in mind, but in practice Neo-Realist hard power politics interrupts this development. Examples of disruptive action include attempts to unilaterally exploit natural resources in the region, settling features in the sea, doing construction work on features in the sea, as well as regular FONOPS conducted by navy ships in the region. Finally, there are difficulties settling on a mechanism for sovereignty settlement, as China makes its claims based on historic- or historical claims, rather than international law as it is written out in UNCLOS.