Looking back on Herman Kahn's predictions, many of them came true. And humanity is the better for them, at least so far. see
As for the boreal lands of Siberia and Canada being infertile, remember when people believed that the Amazon rainforest should be preserved because the tropical soils were too infertile for anything else? Guess what, Brazilian farmers figured out how to grow soy on former rainforest. And some of that soil, in certain river valleys are quite fertile. The Amazon rainforest is not natural, but the result of epidemics started by Europeans and Africans from smallpox to malaria that wiped out these civilisations before conquistadors could discover them. Even in Africa, agriculture is becoming prevalent on savannah land (though much of that agriculture is commercial agriculture benefiting overseas, particularly Chinese interests). So when I see reports of high amounts of microbes and carbon being released when permafrost melts see
http://www.scientificamerican.com/ar...oxide-quickly/, I find that there is more reason for those soils to be fertile (since those soils were quick frozen in one or another of the Pleistocene glaciations and the climate prior to those glaciations was mid latitude deciduous forests) than tropical soils are.
http://www.economist.com/node/16886442 .
I take comparisons to Herman Kahn to be a compliment. Kahn had the courage to say no to the Malthusians and refute them during a time (the Nixon Administration) when Malthusians were at their most fashionable. Malthusianism has a long and dark pedigree. Perhaps the Malthusian ethos started with Chinese gentry who believed that limits enhanced harmony--a justification for forbidding Chinese from building ships that could travel far from China which ended Zheng He's voyages in the 1430s. The French "physiocrats" such as de Quensay got this idea from the Chinese as part of their infatuation with things Chinese and Malthus picked it up from them. Malthus's ideology became popular in the early 19th Century in the British aristocracy. Malthusianism guided British decisions to permit the potato famine in Ireland to kill millions of Irish and a similar famine in India to kill millions of Indians (see
https://understandingevil.wordpress....still-with-us/ ) Later in the 19th Century, Malthusianism got subsumed into Social Darwinism and the Eugenics Movement. see
http://www.artsci.wustl.edu/~anthro/...nIdeology.html .
The Eugenics perspective dominated much of non-Marxist social thought and political economy right up until World War II. Eugenics and scientific racism was something that most educated people outside of the USSR accepted axiomatically, right up until the end of World War II. It was at that point that a Eugenicist named Garrett Hardin apparently recruited a coterie of students, disciples and colleagues, most of whom were young enough not to have been tainted by association with eugenics, such as Paul Ehrlich, former Colorado Governor and current University of Denver Professor Richard D. Lamm and John Tanton to create the current population control wing of the environmental movement, a wing that has also successfully infiltrated the Republican Tea Party with an anti-immigrant agenda see
http://www.splcenter.org/get-informe...Garrett-Hardin . Also see
http://www.amazon.com/The-Legacy-Mal.../dp/0252007905 . It may well be that the nativist aspects of Malthusianism helped to make environmentalism bipartisan during the Nixon Administration, a period in which our formative environmental legislation was written in ways that incorporated a great deal of Malthusian assumptions into law. Such as the Endangered Species Act, which writes into law a) legal definitions of species which have no relationship to scientific reality and b) assumptions about ecosystems which have been found to be scientifically incorrect --species are formed and become extinct a lot more fluidly than was realised in the 1970s--rather like product lines--and extinctions are as often the result of hybridization--barred and spotted owls--pizzlys--as species dying out. So much for "settled science"). Certainly, Nixon made no bones about his Malthusian sentiments. see
http://www.let.rug.nl/usa/presidents...0s/ch20_p4.php . And in Roe v Wade, so did Justice Blackmun who wrote the law (which does not mean that women do not have the right to effective birth control; sometimes we do the right thing for the wrong reasons (see
https://www.all.org/abac/eugen02.htm).
Small wonder that there was a backlash against the more Malthusian aspects of environmentalism beginning in the 1980s that translated into policies such as allowing Chinese women who faced prison for having a second child to get political asylum in the US. Walter Hickel and James Watt attempted to stop environmentalism in it's tracks. But environmentalists were able to retreat into local and incremental action, using the public attorneys general provisions that they had gotten written into environmental law in the US and other Western developed nations to challenge projects that they were able to build opposition to. Which did not stop and indeed encouraged corporations to move environmetally harmful activities overseas to authoritarian nations could and did imprison and kill environmental activists and journalists who supported them. ( A classic example of this is the unchecked pollution that journalists embedded with the US Navy found in the Persian Gulf and reported on before the military could stop them from doing so. US policies against drilling in Alaska and elsewhere contributed to the "drain America last" model that put the US in the position of encouraging dependence on the Mideast, which in the 1980s was relatively easy to defend in return for OPEC nations denominating oil in US dollars and accepting no other currency for oil. Which is where and how our current Mideast troubles began. It seemed like a good idea at the time).
The conservative backlash may have forced the environmental movement to trim it's sails and move away from some of it's more outwardly Malthusian positions but this did not prevent it from learning Saul Alinskian insurgency politics and work at the local level, often making a decent living doing so. Herman Daly explained this as "Think globally! Act locally!". And environmentalists and Malthusians waited for an issue that could put their overall program back on the agenda. Which was what global warming has turned out to be.
In the process of doing this, the environmental movement sucked a lot of political oxygen away from the concerns of the poor and working Americans. Environmentalists were not responsible for the AFL-CIO's abandonment of the Democrats over the nomination of George McGovern in 1972. But they arguably made it easier for the Democratic Party to abandon Labour to the tender mercies of the Republicans, who distracted them with social issues (not the least of which was abortion) while encouraging corporations to break unions in the private sector. While Democrats reinvented themselves as "New Democrats", becoming the party of minorities, the college educated and public employees--and willing to make dishonourable compromises with Republicans on issues from health care to welfare reform that they knew would harm poorer and working class Americans as soon as the Clinton Era boom ended.
So now we come to the question of global warming as it has been put to us. Global warming is an issue, yes. So was the pollution that came out of the post WWII economic boom in the US--and which was finally controlled through pollution control technology. But Malthusians took a very real pollution problem and parlayed it into a particular agenda of how they wanted the US and the world to operate. And they are doing the same thing with global warming--which we CAN live with and prosper with even though we may not want to.