In a tweet he posted shortly before the election, Robert F. Kennedy Jr. took arms against the Food and Drug Administration and its scientists.

“The FDA’s war on public health is about to end,” he wrote, decrying the agency’s “aggressive suppression” of such worthless anti-COVID nostrums as ivermectin and hydroxychloroquine.

“If you work for the FDA and are part of this corrupt system, I have two messages for you,” he continued: “1. Preserve your records, and 2. Pack your bags.”

Donald Trump’s nomination of Robert F. Kennedy Jr., as his secretary of Health and Human Services, which oversees key public health agencies such as the Centers for Disease Control and Prevention, the Food and Drug Administration and the National Institutes of Health, would give Kennedy the power to turn his threat into reality.

That has sent a chill through the scientific community. Serious scientists are understandably dismayed about the damage that Kennedy and Trump could do to the nation’s public health infrastructure — indeed, to public health itself.

“Scientists are facing a huge threat and need to respond, if not for their own well-being, but for public health in general,” says Robert Morris, an epidemiologist and former professor of community health at Tufts medical school. “Academic scientists need to stand together, or they’ll be picked off individually and science will suffer.”

Kennedy is an overt anti-vaccination agitator, among his many other pet pseudoscientific positions. He has called the COVID vaccines, which have saved millions of lives worldwide, “the deadliest vaccine ever made.”

He has pushed the long-discredited claim that the MMR (measles/mumps/rubella) vaccine causes autism. A 2005 screed alleging the link, published jointly by Rolling Stone and Salon.com, was so stuffed with falsehoods that it was retracted by both publications.

Kennedy has voiced the unmistakably antisemitic claim that the COVID virus was “ethnically targeted” by a mysterious sinister force “to attack Caucasians and Black people,” while sparing Jews. He has asserted that chemicals in the environment are turning children gay or transgender, a position he shares with the conspiracy-monger Alex Jones.

Kennedy has elevated threats to the livelihoods of scientists who have resisted his brand of balderdash from the implicit to the explicit. He has talked about firing hundreds of government-employed researchers as a method of remaking the government’s scientific establishment.

The hostility he displays toward government scientists isn’t new.

In a 2021 book titled “The Real Anthony Fauci” — described by the veteran pseudoscience debunker David Gorski as a “conspiracy theory extravaganza,” he absurdly portrayed Fauci, one of the most respected public health officials in America, as a “powerful technocrat who helped orchestrate and execute 2020’s historic coup d’etat against Western democracy.” Fauci’s presumed crime was advocating social distancing and mask policies in the heat of the pandemic.

Never mind that the person in charge of the government’s anti-pandemic policies at that time was Kennedy’s new patron, then-President Trump. Kennedy’s attack on Fauci got taken up by House Republicans as part of their long campaign of slander against scientists involved in COVID research.

To be sure, a few nuggets of legitimate science peek out from within the depths of Kennedy’s world view, as is often the case with conspiracists. His critique of the FDA’s “war on public health” also blamed the agency for ostensibly suppressing “clean foods, sunshine, exercise … and anything else that advances human health and can’t be patented by Pharma.”

At an anti-vaccine gathering in November 2023 when he was running for president, Kennedy called on the NIH to take a “break” from studying infectious diseases such as COVID-19 and measles and to pivot to the study of such chronic conditions as diabetes and obesity.

Such a policy, however, would be based on false premises. The NIH hasn’t downplayed the importance of diabetes and obesity; one of its subsidiary institutes, the National Institute of Diabetes and Digestive and Kidney Diseases, is a key source of funding for clinical trials into diabetes treatments and for obesity research.

If Kennedy wishes to increase such funding, that’s all to the good. But to reduce or suspend funding for research into infectious diseases that can have an acute impact on public health, as though all this research is part of a zero-sum game, would be catastrophic.

Kennedy’s appointment would advance the ideology-based anti-science policies of the first Trump term, when COVID research was stymied for three years.

History provides ample evidence of the consequences of allowing ideology to govern scientific inquiry.

The best example may be the reign of Trofim Lysenko, who gained power over the entire scientific establishment of Soviet Russia beginning with Stalin’s regime and continuing under Nikita Khrushchev. Lysenko benefited from Stalin’s suspicion of and hostility toward scientific experts, whom his henchmen denigrated as “enemies of the people” for their defense of “pure science for the sake of science.”

The principle target was genetics, which the Stalinists derided as “pseudoscientific trash” and subjected to “a one-sided political battle,” as the dissident Soviet biologist Zhores Medvedev wrote in his lengthy examination of Lysenko’s career (smuggled out of the U.S.S.R. and published in the U.S. in 1969).

Lysenko’s key theories harked back to the 19th century naturalist Jean-Baptiste Lamarck, who held that environmentally acquired characteristics could be inherited by offspring — a theory that was exploded by the experiments of Gregor Mendel in the 1850s and 1860s.

Disastrously, the results of his dominance over Soviet science included repeated crop failures. The final estimated toll of famines under Stalin came to more than 7 million of his own citizens. In China, tens of millions more perished in a 1959-1961 famine caused in part by Mao Zedong’s embrace of Lysenko’s policies.

As Medvedev observed, those who wish to undermine science often begin by attacking individual scientists, While Lysenko occupied the highest echelon of Soviet scientific policymaking, “vulgarization, demogoguery, and slander against Soviet geneticists filled both the scientific and the popular press,” Medvedev observed.

These may be extreme examples, but the lesson here is that positioning science as the servant of ideology is perilous.

Childhood vaccination rates for the MMR (measles/mumps/rubella) vaccine have been declining for years, thanks in part to anti-vaccine propaganda purveyed by Kennedy and his ilk.

In 2019, according to CDC figures, 20 states had vaccination rates of 95% or above, 23 had rates of 90% to 94.9%, and only three had rates below 90%. By the 2023-2024 school year, only 11 states were at 95% or higher, 24 were in the 90%-94.5% range, and 14 states were below 90%.

The latter group included the red states Florida, Georgia, Ohio, Iowa, Idaho and Oklahoma. (In California, where state law eliminated exemptions for anything other than a documented medical condition, the rate was above 96% in both school years.)

As vaccination rates decline, outbreaks of vaccine-preventable diseases rise. The CDC counts 277 measles cases in the U.S. so far this year, up from only 13 cases in 2020. The World Health organization and CDC reported only a few days ago that measles cases rose last year to 10.3 million people worldwide, a 20% increase over 2022, largely due to shrinking vaccine coverage.

Even before Kennedy’s nomination, the future looked dire. During the campaign, Trump declared, “I will not give one penny to any school that has a vaccine mandate or a mask mandate.”

As was typically the case, Trump offered no further specifics, but all 50 states mandate not only MMR vaccinations, but shots against polio, diphtheria, whooping cough, tetanus and chicken pox for all schoolchildren. His pledge undermined what might be considered the lone anti-pandemic victory of his tenure, the development of the very COVID vaccines that he later disparaged.

Despite the mandates, many states have taken a lax approach to exemptions, with the result that the nationwide rate for all such vaccinations declined to less than 93% in 2023-2024 from 95% in 2019. That’s alarming, because 95% is generally considered the minimum to produce “herd immunity,” in which vaccination is so widespread that even the unvaccinated are protected from the spread of these diseases.

If the hostility displayed by Kennedy and Trump toward vaccination mandates becomes federal policy, we may well see more and larger outbreaks.

The outlines of a response by the scientific community — including organized opposition to Kennedy’s appointment — are only now developing. Morris has proposed the establishment of a “Science Public Information Network” as a public counterweight to scientific disinformation.

As Medvedev documented, the precondition for destroying public confidence in science is to demean and demonize scientists — as “enemies of the people,” as saboteurs and grifters. Kennedy and Trump have gone down that road.

In a town hall last year sponsored by News Nation, Kennedy complained that “experts” often end up on opposite sides of a debate, which he took as an indication that they shouldn’t be believed.

“Trusting the experts is a function of religion and totalitarianism,” he said. “It is not a function of democracy. In democracy, we question everything.”

Yet our understanding of the science of disease and vaccination isn’t a product of “experts” simply winging it; it’s the product of years of empirical data, all available publicly.

Is the scientific establishment up to the task? Morris isn’t sure. “Most of the people I know are actively deciding whether to go the ramparts or go to the bunker.”