By now, most scientists will have decided for themselves whether or not to participate in the March for Science taking place in Washington on Saturday as well as in hundreds of satellite locations across the United States and around the globe, including 19 Canadian cities.
Organizers say the purpose of the event is to defend the need for well-funded and publicly accessible science, principles that have been challenged in recent months by the rhetoric and budget proposals that have emerged from the White House under President Donald Trump.
"Scientists find it appalling that evidence has been crowded out by ideological assertions and raw opinion," said Rush Holt, head of the American Association for the Advancement of Science, the world's largest multidisciplinary scientific society, and one of many backing the march.
Momentum for the march has been growing since January, fuelled by Mr. Trump's professed disbelief in climate change, talk of gag orders on scientists in federal agencies and a travel ban that has impacted the ability of researchers to work in U.S. labs.
For many, the decision to march was cemented by billions of dollars in cuts to biomedical research that are laid out in Mr. Trump's first budget proposal, released last month. While pushback on the budget is expected from Congress, it has left the research community deeply rattled.
At minimum, tens of thousands are expected to turn up, making for an unprecedented event in the annals of U.S. research, and one that has gone international thanks to the outsize role the U.S. plays in funding science and setting policy on climate change, environmental degradation, pandemics and other science-related global challenges.
At a press briefing this week in advance of the march, Dr. Holt, a physicist and former congressman, stressed that the march is a non-partisan affair. Reporters reacted to this assertion with a level of skepticism worthy of Richard Dawkins confronting a roomful of creationists.
How can a march be regarded as non-partisan when it clearly would not be taking place had Mr. Trump not won last November's presidential election, Dr. Holt and other organizers were repeatedly asked.
"It's not just about Donald Trump.… It's built on a growing anxiety about the conditions under which science can thrive," Dr. Holt said. "If public officials say that alternative facts are the equivalent of facts, or that evidence is optional … then scientists feel – it has dawned on some of them – that it's time to speak up."
Michael Heaney, a political scientist at the University of Michigan, said that both views are correct. The importance of science clearly extends well beyond the interests of one political group or party, he said. But by its nature, the march is far less likely to draw researchers whose politics lean to the right.
"Even if you agree with the issue you just don't want to show up at one of these left-oriented protests because you're just not going to feel comfortable," said Dr. Heaney, who plans to attend the march in Washington together with about 25 volunteer data-gatherers in order to study the degree of partisanship exhibited by those participating. Other researchers who say they oppose Mr. Trump and his policies have nevertheless expressed deep misgivings about taking to the streets at a time when the U.S. political landscape is highly polarized. The risk, they say, is that science will become too closely identified with Mr. Trump's opponents and provide his supporters with an easy way out by declaring the marchers biased.
"I worry that it will have the opposite effect, of pushing people away from science," said Arthur Lambert, a researcher at the Whitehead Institute in Cambridge, Mass., who said he had chosen not to march.
Jeremy Yoder, an evolutionary biologist doing postdoctoral work at the University of British Columbia, said that, on the contrary, scientists have little choice but to publicly decry the threat a Republican-led government in the U.S. poses to the research enterprise.
"There's an entire political party that has decided that part of its platform is going to be removing science from public policy making," said Dr. Yoder, a U.S. citizen who is travelling to Washington for the march.
Such arguments are hardly new to Canadians, who saw thousands of scientists march on Ottawa five years ago in response to Harper-government policies that included lab closures, defunding of environment and climate science and the muzzling of federal researchers.
"It's eerily similar," said Katie Gibbs, who heads Evidence for Democracy, a science advocacy group, and who was a PhD student in biology in 2012 when she became a key organizer of the "Death of Evidence" march on Parliament Hill.
She said there was no question that scientists in the U.S. needed to go public about their concerns and to continue to do so after Saturday's march.
"If you don't keep the pressure on, I don't have faith that any government is going to support science and make evidence-based decisions just because they want to," she said.
The science activism that emerged in Canada during the Stephen Harper era is one reason why some Canadian researchers appear to have readily embraced the U.S. march. But Jason Dumelie, a Canadian researcher based at the Weill Cornell Graduate School of Medical Sciences in New York said there are more direct reasons why Canadians should be vocally supporting the effort.
He notes that the $5.8-billion (U.S.) cut Mr. Trump has proposed for the U.S. National Institutes of Health alone far outweighs Canada's entire federal budget for university-based research across all disciplines.
The cut would have a crippling impact on medical research that would ripple well beyond the U.S. border, he said.
"Canadians benefit from U.S. research almost as much as they benefit from Canadian research," said Dr. Dumelie, who indicated that he would be joining the march in Manhattan.
For John Polanyi, the Nobel Prize-winning chemist and professor at the University of Toronto, the question is not whether to march but what to do about governments that prompt the need for such events.
"Would any historian have predicted that in the 21st century we would need to agitate on behalf of science?" Dr. Polanyi told The Globe and Mail. "We live our lives in total dependency on the fruits of science – for food, health, transportation and communication.
"Science depends on the exercise of reason along with acknowledgment of human fallibility," Dr. Polanyi added. "If that message were ever to be accepted, it would put an end forever to fanaticism and war."