China's leaders would very reluctantly back down if they were truly convinced that the alternative was war with America. But how would the US convince them of that?
It looks as though the United States is going back to its position during negotiations on UNCLOS, and setting aside the carefully balanced nature of the EEZ regime.
Beijing is not just trying to take control of an important body of water. It is trying to take control of East Asia and hopes to use the South China Sea dispute to do that.