Robert F. Kennedy, Jr. writes that “We’re Restoring Public Trust in the CDC” (op-ed, Sept. 3). That would be laughable if it weren’t dangerously wrong. In my view, Mr. Kennedy is waging a war against science and the well-being of the American people.

Let’s not forget. At the height of the Covid pandemic, we were losing 3,000 people every day, hospitals were overwhelmed, doctors and nurses were dying for lack of personal protective equipment, and workers were afraid to go to their jobs. President Trump’s initial poor leadership—free-wheeling behind the podium, recommending untested cures and sowing confusion—exacerbated this crisis.

Yet once the president recognized the severity of the situation, he did something extremely important. He initiated Operation Warp Speed, which in record time led to the development of lifesaving Covid vaccines. Oddly, Mr. Kennedy doesn’t have a good word to say about what his boss called “one of the greatest miracles in the history of modern-day medicine” that “saved tens of millions of lives worldwide.”

Did people make mistakes in responding to Covid? No question. But nobody, not least the secretary of health and human services, should ignore that these vaccines were an enormous and beneficial breakthrough.

We shouldn’t be surprised, however, by Mr. Kennedy’s refusal to acknowledge that success. While the medical community has understood that vaccines are safe, effective and have led to the elimination of polio, measles, smallpox and other diseases, Mr. Kennedy hasn’t. Throughout his career, and as the founder of the antivaccine Children’s Health Defense Organization, he has made millions sowing doubt about the efficacy of vaccines.

If the president wants to make America healthy again, great. But he shouldn’t expect to achieve that noble goal with a secretary who looks down on modern medicine and undermines our ability to respond to pandemics.