Jack Straw: We must confront these new threats to security

The search for collective security has been the inspiration for some of diplomacy's most noble endeavours. It lay behind Woodrow Wilson's 14 points and the foundation of the League of Nations. After its collapse with the onslaught of dictatorship in the 1930s, the ideal found new expression in the great post-war institutions: the Bretton Woods System, the United Nations, Nato and the European Community.

With the end of the Cold War, we finally had a chance to make the aspiration a reality. But the cruel irony is that as our continent has taken historic steps towards lasting peace and prosperity its own neighbourhood, grave new threats have emerged.

International terrorism and the proliferation of weapons of mass destruction threaten to make collective security a redundant concept. How can multilateral institutions guarantee the safety of their members when crazed individuals are prepared to kill themselves in order to inflict mass casualties? How can we claim to enjoy security at home when individuals sheltered by rogue regimes plot mayhem and mass murder in our streets?

Our response to these threats will determine the stability of the world for generations. This is an awesome responsibility. It calls for courageous leadership. And it requires the vision and foresight to act decisively and – if necessary – with military force before our worst nightmares are realised.

In taking such decisions, we are forced to contemplate an eternal moral dilemma. A consequence of military action – however great our determination to minimise the impact on civilian life – is that innocent people may die. We are approaching the moment when the UN will have to make the same calculation in respect of Iraq. For the sake of the Iraqi people, stability in the Middle East, the credibility of the UN and the cause of international law and security it is a challenge we must confront.