The Hazards of Certainty Manifest in Health Policy Today

“Basically, all the scientific leadership has been wiped out at the CDC. They’re all political people now who are running the CDC and determining what the public health message is going to be,” says Julie Rovner. She has been reporting on the CDC for four decades now and has never seen anything like this. Leadership on health policy in the U.S. radiates from Robert F. Kennedy Jr. He is giving a live demonstration of the political advantages and the hazards that come with absolute certainty in health policy.

A Man on a Mission

In The Atlantic, Michael Scherer reports on months of detailed interviews with Kennedy, attempting to answer two simple questions. Why is he so certain he is right and how did he become the most powerful man in American science? After all, he has no scientific training.

The answer is equally simple. He is a man on a mission. He he rationalized his way to absolute certainty that the medical science and public health establishment is utterly corrupt and untrustworthy. A less flattering description might be to describe him as a zealot.

But zeal and conviction have taken him a long way. And for better or for worse, the scientific and public health institutions at NIH and CDC will never be the same. Future policy makers might try to build something from what Kennedy has done, but they will not put it back as it was.

Mistakes and Falsehoods

We are not seeing the first ever mistakes coming out of CDC right now. In obesity, for decades, the agency almost exclusively pushed out an eat-less-and-move-more agenda for dealing with obesity that came with relentless increases in obesity prevalence. It advocated breastfeeding as a tool for preventing childhood obesity despite evidence that it has very little effect on obesity in children. It told adult smokers that vaping is dangerous despite it being vastly safer than their addiction to tobacco smoke.

These were mistakes, but they were not wildly out of touch with the opinions of mainstream scientists. They were politically palatable.

Much less palatable is the current CDC campaign to sow fear, uncertainty, and doubt about vaccines. We know that it comes from sincere beliefs that RFK Jr. holds. But by any reasonable standard of scientific credibility, those beliefs are sincerely wrong.

And the harm that comes from his campaign is already being felt. Children and vulnerable people will die. Previously extinguished communicable diseases are already returning. There is a big difference between mistakes in public health and outright falsehoods.

Mistakes are inevitable and correctable. Outright falsehoods are dangerous and intolerable.

Click here for free access to Scherer’s outstanding reporting on the mission of RFK Jr. in The Atlantic and here for a discussion of its implications.

Robert F. Kennedy Jr. at a MAHA Announcement, photograph by Tom Witham for USDA / Wikimedia Commons

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November 29, 2025