President Trump's efforts to overhaul the Environmental Protection Agency are being cheered by many in the fossil fuel industry who are critics of what they say is excessive regulation.

But many, including scientists and environmentalists, are deeply concerned.

Our William Brangham joins us now with more. William?

Jeff, the EPA's new administrator, Lee Zeldin, has been quite explicit, saying he is, quote,

driving a dagger through the heart of climate change religion. That has meant enormous changes,

ranging from laying off EPA scientists, repealing dozens of rules and regulations, to challenging

the very idea that greenhouse gases endanger human health.

We are joined now by two former EPA administrators.

Christine Todd Whitman headed the agency under President George W. Bush and is a former Republican

governor of New Jersey. And Gina McCarthy ran the EPA under President George W. Bush and is a former Republican governor of New Jersey.

And Gina McCarthy ran the EPA under President Obama, served as a top climate advisor to President Biden.

Thank you both so much for being here.

Christine Todd Whitman, to you first, you and Gina McCarthy have both been, excuse me, Gina McCarthy, excuse me, to you first.

You and Christine Todd Whitman have both been very clear about the dismay that you see at what is happening at the agency that you used to run.

When you look at the scale and scope of what is going on,

what is it that most stands out to you? Well, first of all, you know, I thank Christy for all of her

work and Bill Riley as well. We put out an op-ed just a few weeks ago on this. Look, they are challenging all of the fundamental

tenets of what EPA stands for. First of all, we know that Administrator Leavitt has changed

the mission of the agency from protecting health and the environment to American energy dominance.

Now, how does that work for an agency that's trying to keep people healthy,

that's trying to reduce sources of pollution, and do it in a way that's credible

and consistent with the laws of our country?

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