Well, "consensus" means agreement, and "emerging" means to come out from someplace. The suggestion is that the international community (nations and people all around the world) are beginning to agree on some issues, like the rules of international conduct. The agreement isn't yet complete or solidified, so it is still "emerging" or rising out of the broader pool of conflicting opinions. If China is excluded from international debate and discussions, they are less likely to agree with rules or other international standards and expectations that they had no part in shaping.
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