These words or group of words carry greater weight than they have ever done before, especially within governments and, generally, in civil society. The signals have gone out far and wide and they are beginning to be reflected in actual policies. But, still, too many people are unaware of the vastness of the task ahead, and the interconnections to every sphere of life; this makes the business of tackling these tasks all the more challenging and critical.

Without restrictions on a population’s use or access to natural resources, the very existence of the latter can be imperilled. In many cases, overuse has meant that a resource cannot be replenished. This has happened with natural soil fertility in many places and selected fish species, to take two examples.

At the start of the twentieth century, 1.6 billion people inhabited the earth. In October 1999, the world witnessed the birth of its six billionth child, wrapped in swaddling clothes, in Serbia. The United Nations Secretary General, Kofi Annan, flew specially halfway across the world to welcome the new arrival, to the popping of flashlights, questions flung by the world’s media at him and the rolling of television cameras. The child slept on, safe in the arms of his smiling, young mother, oblivious to the enormous publicity.

In the past fifty years, human population has soared by more than 3.4 billion, putting enormous pressure on the earth’s basic resources: air, water, energy, and land. Environmental, economic, social and political problems have shown a commensurate, dramatic surge, whether in terms of crime or conflicts, food shortages or rising aspirations, leading to political instability.

The critical element is the demographic trigger, when populations sweep past the ability of land, river and air to sustain them. When that trigger is pressed hard, it forces social groups and individuals to move for the sake of survival, at gunpoint as it were, to other areas. Indeed, as Myron Weiner has remarked, migration is the story of our world. People move internally, within nations. People move externally, to other countries, even to poor and underdeveloped lands, which hold out some promise of a living. This puts pressure on the host communities, more so if they are already poor, fearing marginalization by the new, hardworking and mobile settlers. Often, this in turn, leads to a backlash against the immigrant.

Bangladesh represents a classic example of this demographic tragedy. But it is the bloody harvest that has followed since the late 1970s in the remote north-eastern state of Assam, which neighbours that country, that is of special significance. The violence has grown out of an inability by the state and communities to understand or even to begin plumbing the depths of the sheer reactive rage that is spawned by these pressures.