Global human population recently passed six billion. To mark this, the BMJ (formerly the British Medical Journal) published a special edition that was both controversial and innovative. It had 12 complimentary essays, written by leading demographers, epidemiologists, and public health workers. A key issue highlighted was a debate between the non-demographer Maurice King and many demographers, regarding the concept of "demographic entrapment."
King and his supporters argue that the limited reserve carrying capacity of Rwanda was a major factor in that country's devastating civil war, a consequence of which was the release of spare carrying capacity. In contrast to this body of opinion, the key importance of population pressure as a factor in Rwanda's war is denied, not only by demographers but most other analysts of Rwanda.
A second major issue highlighted in the journal was that of overconsumption, particularly of natural capital. The importance of this was partially recognized by the demnographic papers, but none exhibited the sense of urgency concerning this conveyed in the two relevant papers written by epidemiologists and public health workers.
This article discusses relevant sections of the 12 papers with regard to demographic entrapment and overconsumption. In addition, several other examples of demographic entrapment, both historic and contemporary, are suggested and described.
Finally, the suggestion by King that the whole world may be demographically entrapped is refined by consideration of ongoing global environmental changes, both anthropogenic and natural, which are likely to reduce future global carrying capacity. While such changes are, themselves, unlikely to cause global under-nutrition, the negative political and economic consequences of increased regional scarcity, consequent to approaching or passing local carrying capacities, are likely to exacerbate the risk of regional conflict. These areas of conflict could widen, and be aggravated by an increased frequency of natural disasters, predicted by some computerized climate change models. At the worst case, "civilization failure" or "barbarianization" could result. The complex pathway to this, substantially caused by adverse global environmental change, is called global "ecological entrapment.