A Reader's Guide to the Paris Agreement

The greatest triumph of the Paris climate agreement is that there is an agreement at all.

Unlike previous attempted climate treaties, Paris encompasses not only an affluent United States, but also a transformed China and an industrializing India. It even bears the moral imprimatur of the Pacific Island states, countries existentially threatened by sea-level rise.

This global solidarity gives the Paris agreement its power. As I wrote over the weekend, the deal is a strange one. While it will affect policies domestic and international, it is meant to work more as an economic signal than as a binding statute. U.S. Secretary of State John Kerry has said that it sends “a critical message to the global marketplace” to invest in green energy. This signal springs in great part from its unity.

But to reach concord on a single document, the 195 negotiating countries had to address six thorny issues that have long been central to international climate diplomacy. We previewed these last week: They’re often questions of historical responsibility and future ambition which have an additional technical or financial dimension.

The final deal finesses solutions to some of these problems and delays answers to others. exists to handle these questions with care, to revisit them is to get a guided tour of the agreement—a document which will now help decide human civilization’s fate.