Bill Nye leads demonstrators on a march to the U.S. Capitol during the March for Science in Washington, U.S., April 22, 2017. REUTERS/Aaron P. Bernstein

Tens of thousands of scientists and their allies are expected to demonstrate in Washington, D.C., on Saturday, with hundreds of additional satellite marches planned to boot.

Organizers insist the march is simply calling for “political leaders and policymakers to enact evidence-based policies in the public interest.” And yet the sentiments driving it could perhaps only have emerged in the Trump administration: A concern about valid information itself and its role in public policy, combined with deep fear about the fate of federal science budgets, which Trump has targeted for sweeping cuts.

There have, to be sure, been countless past flare-ups at the interface of science, politics, and society. And yet they’ve rarely been so mobilizing for the research world.

“The march is pretty unprecedented in terms of the scale and breadth of the scientific community that’s involved, and it does recall Physicians for Social Responsibility and various scientific groups against nuclear war in the Reagan era, that’s I think the most recent precedent,” said Robert Proctor, a professor of the history of science at Stanford University. “But this is even broader in the sense that there’s a broader perception of a massive attack on sacred notions of truth that are sacred to the scientific community.”

“The current concerns, and let’s say movement, on the parts of many, many scientists and other citizens — and the movements of the current administration — those really do feel pretty unusual,” added David Kaiser, a historian of science at MIT. “And if they’re not completely brand new under the sun, they do feel like a pretty big swing.”

Proctor, Kaiser, and two other historians of science reached for this article cited many partial past analogues for what’s happening in the world of U.S. science right now. But they also noted ways in which the present moment seems distinct. The main reason: While scientists and their allies have argued about and even occasionally protested on specific political topics over the years, taking to the streets in a sweeping defense of scientific truth itself and its role in policymaking seems considerably broader and, for the research world, more fundamental.

On April 22, seven of the 21 kids who are suing the federal government for failing to address climate change attended the March for Science in Washington, D.C. (McKenna Ewen/The Washington Post)

It certainly isn’t news that scientific knowledge is politically potent and tends to get under people’s skin. Many of history’s most important scientists — Galileo, Darwin — clashed with authorities or the dominant cultures of their time.

Nor is it surprising to find that individual scientists can have strong opinions. Albert Einstein took up countless causes in his life, from pacifism to civil rights. Carl Sagan was another celebrity scientist who stood up for many political positions, and especially arms control and resistance to Ronald Reagan’s “Star Wars” program.

The current march, however, is best understood as a key moment in the U.S.’s government’s special relationship with science that began during World War II, and especially after the Soviet launch of Sputnik.

During this era, scientists became deeply attached to the federal government. They helped win wars through military and weapons research. They advised presidents. They also got used to receiving large amounts of public money for more basic and nonclassified research. Meanwhile, an administrative state grew up that relies on technical expertise, not only employing large numbers of scientists directly but also seating them in many formal advisory roles.

In this modern era, there was often friction between science and the American state. There were an unending string of controversies over environmental science (acid rain, ozone depletion, climate change), certain types of biomedical research (fetal tissue, embryonic stem cells), and more. And there were many controversies centered around scientific funding choices as well (Google “Superconducting Super Collider”).

But what’s different about the March for Science and the movement it seems to entail is that it is expressing concern about this modern science-politics relationship in a comprehensive way, rather than on individual issues.

And that corresponds to the Trump administration itself, which has come out of the gates by posing deep challenges to the traditional relationship that scientists have had with their government. Trump is proposing sweeping science budget cuts, even as he’s also raising concerns about the scientific advisory apparatus — the place of scientists in decision-making — by failing to name appointments to leading government scientific and public health positions and aiming cuts at advisory bodies like the EPA’s Science Advisory Board.

And that, in turn, has triggered the sharp scientist response.

“There’s different ways scientists have expressed opposition,” said Harvard science historian Naomi Oreskes. “In history, taking to the streets is kind of viewed as a last resort, it’s not the thing that most scientists would go to first.”

Still, there are notable past examples. Perhaps one of the biggest involved arms control and nuclear weapons, where a large scale political and protest movement reserved a special place for scientists and especially physicists, who had not only originally created the bomb but were in a special position to provide technical critiques of arms policies.

“Arms control is the obvious analogy,” said Oreskes. “And I think it’s the only one that’s really comparable in the sense of scientists not just speaking privately in corridors of power, but taking to the streets. Becoming active in the way that people are doing now.”

In a popular sense, this movement was larger than the March for Science. To give just one example, in 1982, hundreds of thousands of people — perhaps close to a million — attended an antinuclear rally in New York’s Central Park. Obviously, not all of those were scientists, but scientists were central to this movement.

In terms of protests, MIT’s Kaiser sees another example from the past worth comparing: Demonstrations that began on college campuses in the late 1960s, closely tied to the antiwar protest movement, that challenged whether universities and scientists should be taking research dollars from the Pentagon.

“It was about the role of the defense agencies in funding basic research,” said Kaiser. “It wasn’t only the physicists ….It was a fairly broad based coalition that had a lot of passion and a lot of buy-in from students and faculty across many fields of study.” That movement, he points out, was closely tied to the founding of the Union of Concerned Scientists, perhaps the most influential nonprofit and advocacy group operating at the science-politics intersection.

If you look to other countries, meanwhile, you find other relevant examples. In the 1980s in the UK, a group named “Save British Science” sprang up in the face of deep research spending cuts enacted by Prime Minister Margaret Thatcher in the context of a recession.

“Thatcher was quite consistent in her view that all sections of public expenditure should take their share of the burden of cutting public expenditure to meet the recession, and so she cut funding for the research councils, the equivalent of the NSF and the NIH,” said John Durant, a science historian and director of the MIT Museum. “And this caused something close to panic in the scientific community in the UK.” But Durant says the big difference today is that the current movement has a “populist” streak — after all, it’s centered on marching. The British scientists, in contrast, started with a newspaper advertisement.

So as scientists hit the streets on Saturday, they are making history — although it is very hard to say what will come of that intervention.

“I don’t know if most Americans even know what NOAA is,” said Oreskes. “So I think a rally like this is extremely important to making clear to the public, what’s going on … Not because I think it will make Donald Trump change his mind.”

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