As the world's financial powerhouse, the United States has both an outsized effect on climate change relative to our population, but also power to do something about it that extends far beyond our borders. Both treaties and commercial agreements can be used to lever other nations into responsible climate policies; we've been doing this with just about everything else for our entire existence. You ever wonder why weed is illegal everywhere in the world at about the same time? Or copyright laws that destroy the public domain? We did that. We could use that power for good, as well.

It seems like most other developed countries have been taking it more seriously. We could have been part of that group

In developing world, think of all the energy projects since then, that could have leapfrogged the technology directly to renewables. Heck, the extra decade or two of “free” energy could well have altered their economies

The thing is this is China too. I do buy their point that in many ways they have still been a developing country, they still have had so much population to bring forward, so much progress to make, while also being the worlds manufacturer. And when they’re in, they’re all in. Yeah they’ve continued to build coal, and maybe the US being serious about climate change could have influenced that for the last few decades, but everyone needs to remember that while they continued to build coal, they also were taking the worlds biggest steps in Renewables. This could have happened earlier.

Of course, but a country with the means the US have should lead by example. They don't have a "big" responsibility, they have the greatest.