To avoid misunderstandings, let me make my own position clear. I am a paleo-skeptic, as opposed to a neo-skeptic. Neo-skeptics doubt everything except what Science Says; paleo-skeptics doubt everything, period. It is therefore a matter of complete indifference to me whether atheism replaces religion or religion replaces atheism. To a paleo-skeptic (as distinct from a neo-skeptic) the arguments of atheists are as full of holes as the arguments of true believers.
Nigel Barbers' post Why Atheism Will Replace Religion (henceforth WAWRR) is based on two assumptions: that improvement in economic conditions is the major driving force behind the spread of atheism. and that atheism will triumph globally when similar conditions spread to Asia, Africa and South America. Both assumptions are dubious indeed. With regard to the second, it's even dubious whether Europe and North America can maintain their current level of economic development. Plenty of civilizations have suffered economic collapse--why should ours be the one exception? But even if we do come out of the current depression, what difference will that make to the rest of the world? Ever since there's been economic development, it has serviced a minority at the expense of the majority. Used to be, a minority in the developed world was serviced by a majority in that same world. Now inequality has been exported, and a minority of rich nations are serviced by a majority of poor nations. Tout ca change, as the French say. Note that this has nothing to do with the charade of communist versus capitalist; I know of no period or part of the world where prosperity has been spread to all by any economic system.
But let's suppose I'm wrong there. WAWRR, in common with everyone else, fails to see the 800-pound gorilla that isn't stalking the perimeter of the basketball court but sitting right there under the hoop. If by some economic miracle we DID give the rest of the world a standard of living high enough to support atheism, that would bring civilization down faster than anything else. Think of this: with a billion prosperous and five billion relatively or absolutely poor, we're already straining the world's most fundamental resources to the limit. Whether it's arable land, fossil fuels, fisheries or, most crucial of all, potable water. Make a world with six billion prosperous people. and how long do you think those resources would last? By 2050 we will be at nine billion, and that's the optimists' forecast. Before you could say "Robert Malthus" we'd all be at one another's throats, fighting for the minimum necessary for subsistence. Or under an iron dictatorship that would impose an even more unequal distribution of the world's goods than before. If poverty and insecurity drive religion, as WAWRR supposes, either eventuality would create a bonanza for it.
But do they? On closer examination, WAWRR's belief that more prosperity equals more atheism is equally dubious. The crucial counterexample is of course the United States, which until relatively recently was more economically developed than any of the countries WAWRR cites, and where sports and entertainment (claimed by WAWRR to function as religious substitutes) have been more available in more generous quantities than anywhere else. Yet estimates of the percentage of atheists in the U.S. range between an improbably high 9% and .04%. Moreover, the combined populations of the countries WAWRR cites--Sweden, Denmark, France and Germany--amount to no more than about 158 million. The US population is nearly double that. Of course, some will object, if you took the entire population of Europe, that's more than double that of the United States, so WAWRR might still be right in thinking that for a majority of people, the prosperity = atheism equation holds. Sorry, no. First, by taking the whole of Europe you'd have to include countries like Italy (74% belief in God), Poland (80%), Greece (81%), Portugal (81%) and Romania (90%). Even Ireland, after turning itself from a priest-ridden backwater into a computer-savvy powerhouse, holds belief steady at 73%. Second, WAWRR treats the issue as a dichotomy, "atheism" on one side, "God/religion" on the other. What about all those Europeans--close to or even over half in some countries--who do not believe in God or any particular religion but do believe in some kind of spirit, "higher power" or life force? Surely atheists don't want to claim them as co-religionaries? But if they don't, levels of atheism in Europe fall to little more than in the U.S.
In fact, it's quite possible that levels of atheism have remained roughly constant at all times and in all places. Recall that, only four or five centuries ago, you could be burned alive just for having the wrong kind of religion--let alone for rejecting any kind. Now times have changed, and the faith that dared not speak its name has become the faith that won't shut up. I suspect that being able for the first time in history to come out of the closet--a deeper and darker closet than gays ever had to put up with--has a lot more to do with the current "rise in atheism" than any economic circumstance.
WAWR refers to religion as "the opium of the people (as Karl Marx contemptuously phrased it)". Less seldom quoted is the sentence that preceded this: " Religion is the sigh of the oppressed creature, the heart of a heartless world, and the soul of soulless conditions." If that's contemptuous, I'm a monkey's uncle. Marx knew that religion was deeper and more complex than atheists think. Atheists pride themselves on demolishing illusions. Maybe they should begin at home.