A city in peril proved that globalisation can work

When the bombs went off in London on Thursday I was in the city and therefore witnessed one of the greatest triumphs of modern life against the backdrop of yet another heinous crime. Londoners reacted to the disaster not with shock, violence or disarray but with unfailing professionalism, industriousness, concern and - emphatically - civility. There appeared to have been no serious attacks on London's large Muslim population. Rather, there were statements of praise for the Muslim community, for its integral role in London life. There was no rush to judgment, no bluster, no jingoism, only the steady voices of British politicians directing a democratic response to this most undemocratic of deeds.

London showed, even in a moment of real peril, uncertainty and grief, that it is truly, uniquely one of the great centres of world civilisation, one in which all races, religions and creeds can live together peacefully, creatively and productively. I feel about London what I feel about my own home of New York City. Both are what mathematicians call a "proof by existence" - in this case a proof that globalisation can work, that divisions among people according to religion, ethnicity and language can be overcome through a commitment to common purposes among people living in close proximity. London must be the way of the future, of an urbanised, internationalised life in the 21st century for, if not, our crowded world is likely to succumb to hatred, violence and despair.

Tony Blair, the British prime minister, showed leadership yesterday when he declared that the summit's work in addressing poverty and climate change was more important than ever - that the terrorists would not deflect the leaders from addressing economic and ecological problems that threaten the planet and stoke the violence of our times. George W. Bush, US president, spoke well when he declared that an ideology of compassion for the world's poor would triumph over an ideology of hate. Both men owe the world this much and yesterday they delivered. Their war in Iraq was gravely misconceived and dangerous; their words yesterday were constructive.

We are not in a third world war, as some of America's hotheads have believed since September 11 2001. To believe this is to risk making it a tragic reality. In truth, our struggle is not a matter of one culture against another but a struggle for our common survival on a fragile planet threatened by too many weapons; too much environmental destruction; too much poverty and disease; too many young unemployed men in the Middle East deprived of hope and dignity; and too many fundamentalist misconceptions in a world built by science that can be harnessed by ignoramuses and psychopaths. The mobile phone can be both the creator of global connectivity and the detonator of urban mayhem.

We are surely in store for more shocks ahead: terrorist attacks, droughts and other extreme events caused by man-made climate change, disease pandemics and more. Yet we are also better equipped than ever before, with our wealth and technology, to confront these challenges. Our biggest threats are not psychopaths but our ignorance and lack of will. If the new G8 commitments to Africa are now watered down by "political realities" rather than enlarged, if the small steps on climate change are not taken much further, we will pay a very heavy price in the future for this neglect.

Our world is complex. It is as unpredictable as this week's bombings. We must be smart to overcome the risks that we face. A war on terror is needed but only as part of a broader war on poverty, intolerance, environmental degradation and injustice, which fuel so much global instability. The best answer that the world's leaders assembled at Gleneagles can give to Thursday's criminal attack is a shoulder-to-shoulder commitment to address poverty, injustice and environmental destruction in an open, just and meaningful way. To find their way in this profound challenge, the leaders should look to the spirit of London. It is a lodestar for a safer and prosperous world in the 21st century.

Jeffrey Sachs' daily G8 blog can be found at www.ft.com/ sachsblog