The United Nations Climate Summit in Brazil, known as COP 30, will wrap up later this week,

and its achievements will likely be more muted this year.

Tens of thousands of delegates from nearly 200 countries are meeting near the Amazon rainforest.

But among those not there, any official delegation from the United States,

the country that's emitted more carbon dioxide than any

nation on Earth. William Brangham has more for our ongoing climate coverage, tipping point.

The Trump administration's decision to give COP 30 the cold shoulder father's other similar

dismissals of any efforts to combat climate change. The president again pulled the U.S. out of the

landmark 2015 Paris Agreement, which sought to keep global temperatures from rising to increasingly

dangerous levels. So to help us understand where things sit today, we turn to someone with

decades of high-level experience in this realm. John Kerry was Secretary of State

under President Obama and was President Biden's special presidential envoy for climate. John Kerry,

thank you so much for being here. You used to lead large delegations to these COP meetings.

This year, the U.S. administration sent no one.

President Trump says, as you know,

that climate change is the greatest con job in history.

What does it mean when the American government is absent?

Well, I think it means, first of all,

that the United States is hurting itself,

that the absence of U.S. leadership and even presence, just put it at presence, really defeats the fundamental purpose

of these meetings to some degree because no one country can solve this problem by itself. No country has enough money

to solve this problem by itself. That's why it's so critical, and we did in Dubai, in Glasgow,

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