One adage of multilateralism is that effective global accords can be deep and narrow, or broad and shallow, but won’t work if they try to be both deep and broad. The 1987 Montreal Protocol, which controlled chemicals that damage the ozone layer, is a classic example of the former. The treaty’s effects are deep — it’s legally binding on every UN member state and on its own will reduce global warming by as much as one degree Celsius — but its scope is narrow, in regulating a single niche set of compounds.
There have been 25 conferences under the United Nations Framework Convention on Climate Change since the body first met in 1995. Over that period, some 894 billion metric tons of carbon dioxide, about 37% of all greenhouse pollution in human history, has been emitted. What makes anyone think that the 26th meeting starting Oct. 31 — COP26 — will be any more effective?
The answer lies in the age-old challenges of forging major international agreements — and it may be more hopeful than you think.
