In his first term, President Donald Trump touted the “medical miracle” of the mRNA Covid-19 vaccine that he helped deliver to market through the unprecedented public-private partnership known as Operation Warp Speed.

In its second term, the Trump administration is dismantling the signature health achievement of his first term by sowing doubt about the safety and efficacy of the Covid-19 vaccine. The president is taking steps to make the vaccine more difficult for the public to receive and for pharmaceutical companies to bring new mRNA vaccines to market.

Secretary of Health and Human Services Robert F. Kennedy Jr. has been a critic and skeptic of vaccines for years, linking them to autism and other disorders without scientific evidence.

Now, Kennedy is canceling grants to develop more mRNA vaccines, which are also being explored for treating the flu, HIV, and cancer.

He fired all 17 members of the Centers for Disease Control and Prevention’s Covid-19 immunization workgroup, the Advisory Committee on Immunization Practices (ACIP), and replaced them with vaccine skeptics. He removed Covid-19 vaccines from the list of shots recommended for healthy pregnant women and children, which means insurance companies will likely no longer pay for them. The Daily Beast reports that the Trump administration is planning to pull the vaccine from shelves “within months,” citing a close associate of Kennedy’s.

Today, Explained co-host Sean Ramewaram spoke with Katherine Wu, staff writer for The Atlantic, about what this means for Americans’ ability to get vaccinated against Covid-19.

Below is an excerpt of their conversation, edited for length and clarity. There’s much more in the full podcast, so listen to Today, Explained wherever you get podcasts, including Apple Podcasts, Pandora, and Spotify.

What is the secretary of health and human services, Robert F. Kennedy Jr., doing right now with mRNA vaccines?

Probably the latest and biggest news is that he canceled half a billion dollars’ worth of grants to develop more mRNA vaccines. The public is probably most familiar with mRNA vaccines in the context of Covid vaccines. That’s the first place we had successful mRNA vaccines, and that is still where mRNA vaccines dominate the market, but they’ve been in development for tons of other diseases, not just infectious ones, for a very long time. So this is a pretty huge deal.

Remind me who was president when the Covid mRNA vaccine was developed?

Also Trump, just during his first term, not this one.

Oh, weird. How has President Trump advanced his campaign to inoculate and protect Americans with mRNA vaccines in his second term so far?

He hasn’t. During the first term, Trump was the one who helped push forward Operation Warp Speed, that big partnership between government and pharma that got us all of these amazing Covid vaccines in record time, and helped us beat back this pandemic that killed so many people. And so far, this shining beacon from Trump’s first term is being systematically ripped apart. We’ve already talked about how Trump’s administration has pulled funding for development of more mRNA vaccines. You would think that we want to build on that success. Not so much. But they’ve also started to strip away Americans’ access to Covid vaccines. They have removed or altered recommendations to get Covid vaccines in certain groups. They’ve made it harder for vaccine makers to get new Covid vaccines to market, and a lot of the new hires and advisors to the Department of Health and Human Services are taking aim at other Covid vaccine recommendations that could restrict access even further. I think it’s very realistic that within a year or two, very few people will be able to get Covid vaccines, even when they want and need them.

We were all there when the Covid vaccines came out, and the president, I believe, was among the first to get them. They were touted as a miracle of medical science. How is that narrative being rewritten right now?

Yeah, it’s fascinating, right? Trump himself used that phrase, medical miracle. And there’s no scientific reason that he should have stopped believing that. The data on these vaccines has not changed. They’re very safe, very effective. They went through all the normal channels of vetting that get us safe, effective vaccines. But right now in his second term, Trump is leading an administration that is mostly pushing out information that these vaccines are dubious. They don’t work. And largely, this whole system is corrupt. All the people that recommended these vaccines have conflicts of interest and they’re in the pocket of industry, and basically the government is working to restrict access to these vaccines so they don’t hurt as many Americans as they could. He said they don’t work against respiratory viruses, which is not true.

Studies have shown that they saved millions of lives during the pandemic, and they continue to protect people for everyone who was receiving them. He said that they were the deadliest vaccine ever made. There’s no evidence to support that. They have done quite the opposite. And he’s cast doubt on the idea that they were studied thoroughly and carefully vetted by expert scientists who knew exactly what safety signals to look for. None of that is backed up by the evidence, but it’s basically what the federal government is saying right now.

These vaccines were famously brought to market very quickly. I mean, that was part of the miracle we’re referring to here that seemed to spur a lot of these conspiracy theories about their efficacy. Was there any validity to the argument that they were produced too quickly, that there wasn’t enough testing?

I think the way you phrase your question is important, right? Because “too quickly” is about, did they arrive so quickly that there wasn’t adequate time to study them, make sure that they worked well to protect against Covid and they did so in a way that wasn’t posing undue risk to the people who receive them? And I think the answer is very soundly no. It’s important to acknowledge that all this was done on the shoulders of all the vaccine science that came before it. Scientists knew what to look for. They knew how to run these trials. They knew how to scale up their technology. And yeah, they did it in ways that were unprecedented, but not unprecedented in ways that they were shooting in the dark.

So what happens now? You were saying that you can see a future in which even people who want and need these vaccines won’t be able to get them. How far away is that?

I think there are still enough people at federal health agencies that would fight back against that, that it could be a very dragged-out fight. Stripping access to those vaccines instantaneously would also probably come under legal challenge quickly, but I think it’s something that a lot of sectors of the administration are starting to move toward.

Operation Warp Speed obviously played a huge role in developing these vaccines, but it wasn’t just an American effort by any means. If the US is falling off right now and denying the medical miracle that was, what’s the rest of the world doing? And does that mean that you could fly to Canada to get your Covid vaccine, or even get it delivered?

Man, black market international vaccines. What a world. Yeah, it’s a great question, and I think there’s a couple things to touch on here. One is that cutting off funding for mRNA vaccine development here cuts off resources for the rest of the world. The US is extremely powerful in terms of scientific firepower, money, and also, up until very recently, foreign aid. If we stop developing vaccines here, that means there are fewer resources for other countries. There’s also a chilling effect that is very likely to happen if the US says: These vaccines are crap, they’re not worth investing in, they’re not worth recommending, they’re not good enough for our people. Other countries have traditionally taken cues from the US, especially around vaccines. Other countries might look at what we’re doing and pause and be like, well, we don’t want to look weird. We don’t want to be the outliers when the US is doing this.

But are we the outliers right now? It feels like we’re the outliers.

We totally are, and I would hope that other countries look at us and then look at the UK, and be like, Okay, maybe we start following the UK. But it’s tricky, because in a landscape where these vaccines get more scarce and more expensive because the US isn’t pouring resources into developing them, those vaccines simply won’t exist or might be worse than if the US were pouring those resources in. And the US is simultaneously saying “These aren’t good enough.” It becomes an economical and almost political decision for other countries to pause a little bit more.

President Trump has taken to wearing a hat that says “Trump was right about everything.” This is a man who loves a win, and he got a huge one in 2020 with the mRNA vaccine for Covid-19. Why do you think he won’t take the win?

I suspect some of this goes back to what happened at the end of his term and what happened in the ensuing presidential term. The end of Trump’s first term was marred by the start of the pandemic. He was widely criticized for letting things get as bad as they did in the US in those early days. Even though he helped push vaccines along, that was a triumph that didn’t completely overshadow all of the other policy hiccups that made 2020 and much of 2021 horrific in this country. The pandemic could have gone much better here if there had been a much better coordinated public health response and better communication. I think a lot of Trump’s base felt angered by that, and they felt angered by a lot of early pandemic policies. They felt betrayed by the government, and I think that has soured Trump’s base on all things Covid, including vaccines.