It was a very strange turn of events for China to be playing host to a UN biodiversity summit in Montreal, at the end of a year in which its relationship with Canada has grown increasingly tense. …Even more improbable is that this makeshift arrangement…  in which China seemingly played a constructive leadership role despite the potentially embarrassing circumstances, might also be cause for some optimism about the place it will occupy in international environmental relations in the future. No matter how much other countries need to safeguard themselves against various forms of aggression by a Chinese government shifting further into autocracy, the climate and ecological crises are not going to be solved without the planet’s second-largest economy playing a role. …There’s now a sense that China might be able to help build bridges over divides that perpetually threaten to derail global environmental progress. [to access the full story a Globe and Mail subscription may be required]