David Attenborough, BBC television's respected documentarist of the natural world – who resembles every young person's ideal grandfather – is the latest in a growing roll-call of public figures asserting that climate change is the major challenge facing the world. His motivation is clear: "One of the things I don't want to do is to look at my grandchildren and hear them say, 'Grandfather, you knew it was happening – and you did nothing'."

Preserving the planet for our children and grandchildren speaks to our deepest aspirations, no matter what culture, religion, or ideology we belong to or espouse. The entire global political system has been fruitlessly distracted for nearly half a decade by 9/11 and its consequences. It is not just that the United States-led "war on terror" fails to address the real threats facing humanity; the very conduct of that "war" is exacerbating these very threats, and bringing closer the likelihood of their devastating impacts on human and environmental security.

This is the stark conclusion of a report from the Oxford Research Group (ORG), Global Responses to Global Threats: Sustainable Security for the 21st Century, published on 12 June 2006. The report – co-written by the ORG's research officer Chris Abbott, author of the ORG's international security monthly briefing (and openDemocracy columnist) Paul Rogers, and myself – identifies four main threats to security in the next century and outlines a plan of action. The four threats are:

• climate change
• competition over resources
• marginalisation of the "majority world"
• global militarisation.

If these growing threats are not halted within the next few years, the world could pass a tipping-point which would catapult it into a period of intense and unprecedented conflict.

John Sloboda is executive director of the Oxford Research Group

The ORG's report Global Responses to Global Threats: Sustainable Security for the 21st Century – co-written by Chris Abbott, Paul Rogers, and John Sloboda – is published on 12 June 2006

Also by John Sloboda (with Chris Abbott) in openDemocracy:

"The 'Blair doctrine' and after: five years of humanitarian intervention"
(22 April 2004)

A brief look at each of the threats is enough to suggest the scale of peril they present.

First, climate change will cause rising ocean levels, placing migratory pressures on millions of the world's most vulnerable people living on coastal and river delta areas. It will also alter rainfall patterns, particularly over the tropics, creating drought and food shortages. Hurricane Katrina gave a small foretaste of much worse to come.

Second, the world's oil reserves are depleting, and there are severe water shortages in many parts of the world. Yet the major powers act as if these resources are unlimited: aggressively competing for their control and expanding their consumption, rather than seeking alternatives. Nuclear power is promoted as a magic wand, rather than a growing source of deadly materials for those states and terrorist groups wishing to manufacture nuclear weapons.

Third, disparities of wealth and power are growing deeper, both within countries and between different regions of the world. This fuels the discontent and marginalisation which feeds political violence. Yet current trade and aid arrangements do little to address global economic inequities.

Fourth, far from "keeping the peace" the unceasing growth in global military expenditure is stoking fresh conflicts. New weapons, such as "mini-nukes", are destabilising current arms-control regimes such as the nuclear non-proliferation treaty (NPT), and place more deadly capabilities within the reach of terrorists. The civilian deaths caused by the United States and the United Kingdom in Afghanistan and Iraq have been a propaganda gift to al-Qaida.

The leaders of the two states, George W Bush and Tony Blair, may have made a reluctant admission of tactical errors in Iraq, but there is no fundamental review of the effectiveness of their current military strategy. Nor are there serious efforts to curb or decrease military expenditure by any major power; the record of Chinese arms sales in stoking conflicts in Sudan, Burma, and Nepal is but one example of how the opposite has been happening.

These four trends, individually and when reinforcing each other in combination, put the world on course for catastrophe.

It's up to us

There is, however, one big hope. That hope lies in the people of the world who are waking up to this impending disaster, and the pressure that only they can place on governments. The spread of education coupled with increasing global communication means that more and more people see, with greater clarity, the dire consequences of our actions and the need for alternatives. This new global awareness has thrown up three powerful social movements, which have united people across the world:

• the environmental movement
• the global justice movement
• the peace movement.

Until now, these movements have operated relatively separately, and with differing degrees of purchase on the behaviour of political and economic elites. Now is the time to recognise that they are three indispensable pillars of a broad unified movement for global survival. No one movement can succeed without the others.

We cannot achieve disarmament without climate control. We cannot have clean water for everyone without trade justice. We cannot eliminate terrorism without developing alternatives to oil. All of these linkages are components of a "sustainable security" approach to the world's problems.

The main feature of this approach is that it does not attempt to unilaterally control threats through the use of force ("attack the symptoms"), but rather aims to cooperatively resolve the root causes of those threats using the most effective means available ("cure the disease"). The approach is preventative, in that it addresses the likely causes of conflict and instability well before the ill effects are felt, rather than waiting until the crisis is underway and then attempting to control the situation, at which point it is often too late.

Is this achievable? Not if we simply wait for governments to act. They are too focused on their own narrow national and economic interests. Community groups, faith groups, NGOs, and many other elements of civil society (including journalists) will need to coordinate their efforts to convince governments that this new approach is practical and effective, and is the only real way to ensure security.

We citizens of the first decade of the 21st century have both an awesome responsibility, and an unprecedented power to act together. What we decide in the next five-to-ten years could change the future of this planet more profoundly than any other period in recent history. The stakes have never been higher.