A vision for a new world order based upon co-operation and springing from today's interdependence of nations and peoples was the Prime Minister's call to arms at Labour's conference.
Yes, the international situation is dangerous and could become more so. But the reaction to the terrorist attacks on the US contains hope for the most fundamental re-alignment of global politics since the beginning of the Cold War.
Shock and horror reverberated around the world as billions watched the guided-missile airliners smash through New York's twin towers on television. It generated an immediate torrent of revulsion against the terrorists, and also deep sympathy for the American people.
The unity of the world has been quite unprecedented: from Nato and the European Union to Russia and China. General Musharraf's brave decision to sign up Pakistan was particularly significant.
Of course no one knows how fast that will hold as the coming military action unfolds. The military task is difficult. But instead of being alone and beleaguered, the US has felt quite the opposite. Instead of the hawkish response many expected, it has been cool and careful, planning systematically for targeted and appropriate action. Domestic pressures within the US for lashing out have been muted.
Those who claim London is merely coat-tailing Washington couldn't be more wrong. Because Tony Blair has been through the Kosovo war – with all its dangers and fraught uncertainties - and because he has been so steadfast in his support for President Bush, his influence is considerable. Theirs is a dual-carriageway partnership, not a one-way street.
Speaking at the Labour Party conference, the German Chancellor, Gerhard Schröder, also underlined that backing from all of us in the European Union will be steadfast, not flaky as some had all too eagerly speculated. President Chirac's visit to the US signalled the same.
This is an opportunity for the EU to be taken seriously in Washington too, not just as an economic but a global political force, helping to achieve peace in the Middle East and promote an end to the roots of conflict worldwide.
Perhaps even more important, have been the unprecedented developments elsewhere. This is the first time that Russia has co-operated on such a scale, both diplomatically and militarily, in a region of great sensitivity to them. It is the first time China has been very supportive, laying aside many of its usual reservations about international military action. It is also the first time that Japan has offered logistical support for such action.
Before 11 September, who would have predicted that President Putin would have asked for a structured link to Nato on a common security agenda as he did this week? Who would have predicted that the United Nations Security Council would unanimously decide to oblige all members of the UN to take tough measures not only against those who finance terrorism, but also to outlaw safe havens for terrorists and to support action to destroy their capability?
This is big stuff. It could and must presage international solidarity on other threats to world peace and stability, from climate change to the proliferation of nuclear, biological and chemical weapons. It could and must presage a new agenda to tackle world poverty and debt, to open up trade, remove protectionist barriers against poor countries, and curb arms exports for external aggression or internal oppression.
If maintained and strengthened, the very solidarity shown to the US could help to promote an end to the spirit of unilateralism and isolationism, especially on Capitol Hill. This could encourage a new consensus over multi-lateral agreements, something which is desperately needed.
Historically, when Europe and the US have stood together, the world has always been a safer place. It would be safer still if other key countries, including Russia and China, were able to join us in a new lasting alliance, not just against terrorism, but in favour of a progressive new agenda for international peace, stability and prosperity.
Its immediate task will be to go beyond a military coalition. Our war is not with the Afghan people. Their country, ravaged by conflict and drought, was gripped by a humanitarian crisis before the terrorist atrocities in the US.
The international community must work together to minimise the suffering of the Afghan people and to ensure them a peaceful, stable and free future in their country. That means helping to rebuild Afghanistan after its terrorist bases have been eliminated, not just with food aid but with development assistance for infrastructure, jobs, hospitals, schools and homes.
Nobody witnessing the attacks on the Pentagon and the World Trade Centre could have doubted the seismic nature of their impact upon global affairs. But the emerging new agenda could enable that terrorist barbarism to be turned from a threat to Labour's vision of a world based upon equality, justice and human rights, to an opportunity to help realise that vision. We must make sure it is.
The author is Minister for Europe and MP for NeathReuse content