We all know that even in the United States the guarantee of free speech has limits. The Supreme Court long ago said that no one has the right to endanger his or her fellow citizens by, for instance, falsely yelling “fire” in a crowded theater. Such acts of speech are said to pose “a clear and present danger.” James Hansen, perhaps the most respected climate scientist on the planet, thinks that the fossil fuel lobby and its disinformation campaign about global warming may pose a similar threat.

Hansen, speaking before the U. S. Congress last week, said that the CEOs of fossil fuel companies should be tried for “high crimes against humanity and nature.” He said they deserve this fate because they know full well that continued burning of fossil fuels threatens the stability of the climate and with it civilization. Yet, they purposely confuse the public to forestall the day when limits will be placed on carbon emissions from such fuels.

(A later decision by the U. S. Supreme Court narrowed the test for prohibited speech to that which incites or is likely to incite “imminent lawless action,” and so there is absolutely no danger that fossil fuel industry executives will ever be prosecuted for what is now legally regarded as protected political speech.)

Why does Hansen speak in such seemingly hyperbolic language? He does so because his own research suggests that the highest advisable level of carbon dioxide in the atmosphere is 350 ppm. The current level is already 383 ppm and growing by 2 ppm each year. We have passed a critical point in the global warming saga, and we must now retrace our steps. Hansen therefore believes we must actually find ways to reduce not the growth of emissions, but to reduce emissions altogether to a point that will allow greenhouse gas levels in the atmosphere to fall.

This he says must happen quickly, and the reductions must be drastic or we will face catastrophic consequences, ones that will become unstoppable long before they actually occur because of the delayed effects of carbon emissions. These consequences include worsening floods and droughts, much higher shorelines, massive extinction of species, possible rapid climate shifts in parts of the world, and other problems that will threaten the food, water and general well-being of all humanity.

But public discourse on global warming is being muddied. Here in the United States it is a matter of faith that the cure for faulty free speech is more free speech of the factually correct kind. It is the only response truly anticipated by the U. S. Constitution. There is unfortunately the slight problem that the fossil fuel industry has huge sums of money with which to pursue its freedom of speech in the media. There is another problem in the case of global warming, namely urgency.

For comparison let me offer a brief recap of an historically important issue in American history. It is a great injustice and disappointment that women did not obtain the right to vote after the Civil War along with freed male slaves. It was a disappointment because so many women had worked so hard for abolition. It took another half century of advocacy before they were finally granted that right. While no one should minimize the struggle for woman’s suffrage in the United States, it was a struggle–however painful and filled with injustice–that could wait for the principles of free speech to be vindicated without endangering all of humanity. But the amplified free speech of the fossil fuel industry’s disinformation campaign does indeed threaten all of humanity. And, the outcome of the struggle between the forces of change and reaction cannot wait 50 years to be resolved on the side of right. By then all the worst damage will be inevitable.

There are so many other issues which fit into this category as well: the depletion of fisheries; the destruction of soil; the peaking of oil; the catastrophic loss of biodiversity due to logging, modern industrial agriculture and urban development; the poisoning of the water, air and food supply with toxic chemicals; and the depletion of precious fresh water. Most of these issues are interlinked with global warming and with each other to one degree or another.

As the clock ticks down to tipping points for each of these problems, will the cherished principles of an open society be challenged? Will those principles continue to be used to delay or water down action and thereby threaten the lives and livelihoods of billions? Or will those principles be modified in some way that allows free speech, but limits the amplified kind that huge sums of money can buy in the modern media?

If we had 50 years to debate all these problems, I am certain that the side espousing sustainability would win. Given the urgency with which I believe we must address these issues, is it an acceptable outcome to be able to say “I told you so” at some future date as modern society crumbles in the face of these challenges?

I don’t claim that the issue of free speech and the enemies of sustainability is an easy one for those of us who embrace the notion of an open society, that is, a society where no one is presumed to have a monopoly on truth and where we work together sometimes even through the violent clash of opinions to advance the search for truth. What the ecological and resource challenges we face now call into question is whether an open society is capable of making the kind of change we need to make as quickly as we need to make it.

One could argue that ours is not an open society, but rather one dominated by corporate power and that it is corporate power that must be reigned in as part of the process of moving toward a sustainable society. But once again we are faced with the time problem. How long will it take for the normal processes of a nominally open society to bring corporate power to heel? 10, 20, 50 years?

The path for most people interested in creating a sustainable society is to start creating one. But will the powers which are working against such a society make those efforts moot? And, if that is the case, with so much at stake, is there a third way of addressing free speech that preserves the basic principles of an open and democratic society, but still allows for those who have the evidence and the logic on their side to prevail in time to avoid the worst?

So far, I have yet to find such a way that does not destroy the very open society I seek to preserve.