Opinion | Will the Glasgow Climate Summit Be the Breakthrough We Need?

This seemingly weaker approach had a surprising result: It produced greater global ambition. With the pressure of mandatory targets lifted, nearly every country made commitments to tackle the problem. Far better prepared this time, the Obama administration negotiated directly with China, and both countries offered bold pledges to reduce emissions.

This approach culminated in late 2015 with the Paris Climate Agreement, gaveled into existence in a huge plywood conference hall outside Paris, where cheers rang out and Champagne flowed. Climate change was now seen as a problem every country had a responsibility to tackle.

Even so, the national pledges made at Paris were wholly inadequate. If met, they would still have allowed global warming to rise to dangerous levels. Recognizing this, the delegates in Paris adopted a “ratchet” mechanism, requiring countries to show up every five years and make new, bolder pledges. That was supposed to happen in 2020, but was delayed a year by the pandemic. So it is in Glasgow this year that the first new pledges come due.

Britain, which is hosting the conference, is cajoling the world’s countries to go big. Many of them say that they will cut their emissions close to zero by 2050 or 2060, and the bold ones are setting 2030 targets. That is important, because tough 2030 targets make procrastination harder; they demand action from the politicians who are now in office.

Emissions in the United States have already fallen about 20 percent from their peak in 2005. Much of that effort was carried out by state and local governments and by industry, the real workhorses on this issue in America. President Biden has pledged to cut national emissions in half by 2030, compared with 2005 levels, and largely eliminate them by 2050. But he has had trouble muscling his plans through Congress and arrived in Glasgow nearly empty-handed.

Given the long and troubled track record of these international negotiations, have they had any real value? The best way to view the history is to say that nearly a quarter-century of failure has been followed by six years of moderate success.

The world’s international institutions and global treaties are inherently weak, and the climate agreement is among our weakest treaties. And yet it offers, in these regular meetings, a stage on which the climate drama can play out.