Last week I traveled down to Mexico City as part of a delegation led by my colleagues Michael Levi and Shannon O’Neil to discuss climate change issues with Mexican officials and civil society leaders. Aside from discovering that Mexico City is beautiful, I found that the Mexicans are “all systems go” as they prepare for the next round of climate negotiations to be held in Cancun in December. They are determined to ensure that the Cancun round avoids not only the logistical nightmares but also the political pitfalls of the Copenhagen meeting. For that to happen, they need a modicum of cooperation and constructive participation by both the United States and China. Unfortunately, it doesn’t seem that either country is getting the point.