[The Conversation Africa] South Africa recently hosted a Brics summit. The event attracted international attention because the group has recently begun to emerge as a possible rival against US dominance of world affairs. The US and China lie at the heart of this debate. They are the two biggest trading partners of most African countries and both have strategic interests that they are determined to protect. The Conversation Africa's politics editor, Thabo Leshilo, asked international relations expert Christopher Isike to explain.