You make an excellent point about China and how its economic needs direct its foreign policy. It would be a major extension of their power to involve themselves in Africa to the extent you are describing. However their needs are huge and they are building a great navy to project power. Sub Sahara Africa is evolving with a militant Islamic population in much of the North and a largely Christian population in the South. As you point out the resource rich central area where they clash will be contested and the scene of continual bloodshed. If the Chinese establish a harsh peace, it would benefit the less aggressive Christians.
The role of China in Iran is also overlooked.China views Iran as a natural source of energy. It also views its seventy million citizens as a potential huge customer base for its export driven economy. It has absolutely no fear of a nuclear armed Iran, and knows the mullahs are not so foolish as to support China’s radical Muslims. Most importantly China bitterly abhors American political, military and economic intrusions in Asia. It bitterly resents the American imposed sanctions. Americans do not realize how Asians deeply resent foreigners ( read that white Europeans) involving themselves in Asia. The rational for WWII for the Japanese common citizen and most intellectuals was that Asia was humiliated by the British, French, Dutch and Americans not only economically dominating but directly ruling. Japan of course saw itself as Asia’s dominant and natural leader. China now views itself as such. Its inherent anti-American postures and actions in Asia should be viewed in that context.
You are also absolutely right about how most Westerners barely begin to understand Asian politics and culture. We think in terms of years or at most decades; the Chinese think in terms of centuries or millennia of their historical role in the region.
China's views of international relations are not those of America, or of the former Soviet Union, or of the European colonial powers before the Cold War. On the contrary, they are based on an attitude of Chinese cultural superiority dating back well beyond half a millennium before Chinese relative power began to decline in the 1600s vis-a-vis the West, and quite probably for thousands of years before that.
The simple fact of the matter is that China is one of the world's oldest civilizations. While modern Egypt and modern Syria and modern Iraq and modern India have varying levels of (often distant) connections to their ancient cultures, modern China is unquestionably the heir of a culture which, even in the few cases when it was conquered from outside, absorbed the conquerors rather than being radically changed by them.
To show just how old Chinese civilization is, I often point out that my Italian ancestors were living in caves in what would someday become the Etruscan kingdom predating the rise of the earliest Roman kings before the Roman Republic, and perhaps watching a few passing Phoenician ships whose captains considered the Italian peninsula full of worthless barbarians, at the same time China had large cities and strong central (or at least regional) governments. Even before that, Abraham left Sumeria as a wandering nomad who herded animals in what is now Israel, long before the rise of the Assyrian or Babylonian Empires, during a period that the Chinese already had shipping and trade with other parts of Asia.
Despite five centuries of self-isolation of the Chinese, I think it is obvious that the current Chinese leadership has decided the Chinese have no choice but to participate in the world economy, and that means China must have secure access to natural resources. If China were to decide to intervene anywhere in the near future to secure resources for itself, South Sudan would be the place.
Will China do that? I'm sure it would regard such action as a last step, not a first. But I can't see China tolerating a return to the North-South civil war in Sudan given the amount of time and effort they've spent in trying to get oil out of that part of the world.
This, unfortunately, is probably going to be a situation where we as Americans can't do much beyond watch and wait. We do not have a compelling national interest there.
China may.
And if they decide they do, that decision will have region-changing consequences, some of which could actually be good.
But long term, I think we have good reason to be concerned about Chinese intentions. Their power is growing, ours is not, and a decisive demonstration in the Third World of Chinese willingness to take military action could create an entirely new set of problems for the United States.
That is especially true if, post-2016, American power continues to decrease and various Third World nations decide it's easier to work out a commercial deal with the Chinese than to bother with American vacillation and weak presidencies.
I do not believe Americans have even begun to comprehend the amount of damage that President Obama’s perceived international weakness will do by opening the doors for others to act, not necessarily because they want to do so, but rather because they believe we will not.
I'm thinking primarily of Israel and South Korea when I say that — both are already taking actions based on the perception, probably true, that if things get really bad they're pretty much on their own. But China deciding to act outside its traditional sphere of influence in Asia would be a game-changer in many ways, not so much because of the initial action, but rather because of how others would react if China acts and America doesn't.
Perceptions count in world politics. That is especially true in some of the world's bad neighborhoods and trouble spots.