KYIV— Will a trade deal be reached between the US and China? At present, we cannot be sure. The obstacles are high. But far bigger questions arise. Would a deal, if reached, stabilise conditions for trade between the two superpowers? Would stabilising those conditions ensure co-operative relations between China and the US? The answer to both questions is no. A deal would not even mark the end of the beginning of US-China frictions. It would be just a small step towards redefining this relationship.