Wars between civilizations, religions, nation states, and the such were all attempts to create an order that reflected a world that was best for the subjective entity. If factions in China went to war, they did so against other factions, against the state (a separate entity), or against a group or faction of another state (by which I mean Nation-State) outside of China, or with the whole of other state altogether. China simply created a isolationist state and only created an order (I wanted to use peace but that might be a completely different conversation altogether) that limited their world involvement to dealings within those borders; they would then have their world-view being served through their actions. During World War II, the United States of America took control as the hegemon and began creating a world that would most benefit its view on how the world should be for U.S. interests, though not without objection from other entities.
That said, at this point, less wars occur on a general scale because most civilizations, as defined by Samuel Huntington, have been able to create domains that keep other actors in the world from trying to reshape the world through physical borders. Since the Russian Revolution there has been a different proliferated idea, that is as old as it is new, to changing the world through economic, political, and cultural systems. Nevertheless, civilizations as a whole are able to have a domineering nation-state that is able to protect the interests of the civilization, through a unified agreement, whether written or not, that calls for the protection of the people and associated cultural influencers from other civilizations. Those could be economic, political, religious, or other cultural influencers.
Alfred Wegener was an astronomer, geophysicist, meteorologist, and climatologist, born in November of 1880. Wegener earned his Ph.D early in life and between researching polar air circulation and lecturing at university he wrote on other topics of interest. One such interest while at Marburg was that of identical fossils of fauna and animals found on opposite sides of the Atlantic, i.e. East United States and Western Africa. Wegener's theory of "continental drift” was supported by this simple placing of the pieces together, so to speak. The continents had formed a single mass, called Pangaea (Greek for "all the Earth"). Through shifting of what we now understand to be tectonic plates, the continents are moving away from each other. This was not a new theory, but given his wide array of specialties, Wegener was able to use multi-disciplinary study to prove these connections. Years later, through Globalization, we have now seen a reversal of continental drift.
What we have as a result is a world that is smaller but still defined by "civilizations" that encompass large cultural identities. The archaic labels of American, Asian, African, and European will encompass those peoples of their respective continents. It will be interesting in the future to see how people define themselves, and whether traditional applications of identification will apply.
**This was written half-asleep after dreaming of Pangea. Please pardon this mess I call writing.