Some of the most powerful conservatives in the United States have, since the beginning of the Covid-19 pandemic, chosen to sow disinformation along with mockery and distrust of proven methods of combating the disease, from masks to vaccines to social distancing. Their actions have afflicted the nation as a whole with more disease and death and economic crisis than good leadership aligned with science might have, and, in spite of hundreds of thousands of well-documented deaths and a new surge, they continue. Their malice has become so normal that its real nature is rarely addressed. Call it biological warfare by propaganda.

Call Jared Kushner the spiritual heir of the army besieging the city of Caffa on the Black Sea in 1346, which, according to a contemporaneous account, catapulted plague-infected corpses over the city walls. This is sometimes said to be how the Black Death came to Europe, where it would kill tens of millions of people – a third of the European population – over the next 15 years. A Business Insider article from a year ago noted: “Kushner’s coronavirus team shied away from a national strategy, believing that the virus was hitting Democratic states hardest and that they could blame governors.” An administration more committed to saving lives than scoring points could have contained the pandemic rather than made the US the worst-hit nation in the world. Illnesses and casualties could have been far lower, and we could have been better protected against the Delta variant.

At the outset of the pandemic, as Seattle and New York City became hard hit, Republicans apparently imagined that the pandemic would strike Democratic states and cities first, and certainly in 2020 Black, Latinx and indigenous people were disproportionately affected. To put it clearly, Republicans enabled a campaign of mass death and disablement, thinking it would be primarily mean death and illness for those they regarded as opponents.

Nevertheless, Democratic governors, Native nations and people with moderate-to-leftwing views have done a better job of protecting against this scourge. The worst-hit areas in the country are now Republican-led states and regions. At one point recently, Florida under raging science denier Governor Ron DeSantis, with about 7.5% of the US population, accounted for 20% of all new Covid cases. The governors of Florida and Texas have banned mask mandates, making attempts to protect public health, including that of children, acts of defiance by cities and school districts. DeSantis’s supporters are peddling “Don’t Fauci My Florida” T-shirts and drink coolers with the text “How the hell am I going to drink a beer with a mask on?” On 27 July, as Delta infections proliferated, House minority leader Kevin McCarthy tweeted, “Make no mistake – The threat of bringing masks back is not a decision based on science, but a decision conjured up by liberal government officials who want to continue to live in a perpetual pandemic state.”

Call Tucker Carlson and Laura Ingraham the spiritual heirs of Lord Jeffery Amherst, the British military commander who in 1763 wrote to an underling, “Could it not be contrived to send the Small Pox among those disaffected tribes of Indians?” As the New York Times put it with characteristic mildness, “Mr Carlson, Ms Ingraham and guests on their programs have said on the air that the vaccines could be dangerous; that people are justified in refusing them; and that public authorities have overstepped in their attempts to deliver them.” Newsweek was more blunt, quoting Ingraham herself saying that the vaccine was an attempt to push an “experimental drug on Americans against their will – threatening them, threatening to deprive them of basic liberties, if they don’t comply.” The goal was to rile up the audience – and prevent them from getting vaccinated, while the evidence was clear that the vaccines prevent both disease in the vaccinated and the spread of disease. Vaccines are, incidentally, how smallpox was eliminated worldwide.

There is of course another angle to the conservative response to the pandemic. In far-right ideology, freedom – for white men especially – is an absolute goal. Even recognizing the systems in which we are all enmeshed might burden the free person with obligations to others and to the whole. Science itself is a series of descriptions of our enmeshedness: of how pesticides travel beyond the crops they’re sprayed on, of the way that fossil fuel emissions contribute to health problems and climate change, of how the spread of disease can be prevented by collective action. Rightwing ideology, after all, has emphasised the right to own and carry a gun over the right to be free of being menaced or murdered by guns, as thousands are in the US every year.

But just as the right to brandish guns is defended in the face of those gun deaths, so the right to contract and spread a sometimes lethal and often debilitating disease is defended as the antithesis of the responsibility not to do so. It’s safe to assume that the Republican leadership knows better, and that some of their followers do and some don’t. Some have chosen to engage in biological warfare; some are merely tools being used in that warfare. That is, some of them are unwitting corpses being catapulted over the walls, unconscious smallpox blankets; some of them are Amherst in spirit. Those using fake vaccine cards – as college students, and two recent travelers from the US to Canada have – are definitely Amhersts.

Covid-19 is far from the first time people have decided to profit from promoting the death of others: the fossil fuel industry plunging ahead while fully aware that climate catastrophe was the consequence of its product is the most extreme example. Manufacturers of guns and prescription opiates have done so as well. But it might be the first time that a new threat has been so dramatically increased not by direct profiteers but by those selling ideology and sowing division.

Measuring the impact of the pandemic by its death toll leaves out other impacts that matter: millions of schoolchildren isolated and undereducated, millions of parents exhausted by double duty, millions of small businesses shuttered, millions unemployed and impoverished, their dreams crushed, millions isolated and anxious, millions grieving the dead. Medical workers who were selflessly heroic the first time around are demoralized now that the hospitalised are so often people who could have been vaccinated, could have been careful, but chose not to. The poison runs through everything. Some of it was spread on purpose.

• Rebecca Solnit is a Guardian US columnist. She is the author of Men Explain Things to Me and The Mother of All Questions. Her most recent book is Recollections of My Nonexistence