'Terrorism will not be defeated without peace in the Middle East, where poison is incubated'

This is an edited version of Tony Blair's speech to the joint session of Congress:

Mr Speaker, Mr Vice-President, Honourable Members of Congress. Thank you most sincerely for voting to award me the Congressional Gold Medal. Let me also express my gratitude to President Bush. Through the troubled times since 11 September changed the world, we have been allies and friends. Thank you, Mr President, for your leadership.

I feel a most urgent sense of mission about today's world. 11 September was not an isolated event but a tragic prologue. Iraq; another act; and many further struggles will be set upon this stage before it is over. We are bound together as never before.

This coming together provides us with unprecedented opportunity but also makes us uniquely vulnerable.

The threat comes because, in another part of the globe, there is shadow and darkness where not all the world is free, where many millions suffer under brutal dictatorship and poverty ... and because in the combination of these afflictions, a new and deadly virus has emerged.

The virus is terrorism, whose intent to inflict destruction is unconstrained by human feeling; and whose capacity to inflict it is enlarged by technology. This is a battle that can't be fought or won only by armies. Our ultimate weapon is not our guns but our beliefs.

The spread of freedom is the best security for the free. It is our last line of defence and our first line of attack. In some cases, where our security is under direct threat, we will have recourse to arms. In others, it will be by force of reason. But in all cases to the same end: that the liberty we seek is not for some but for all. For that is the only true path to victory.

The risk is that terrorism and states developing WMD come together. When people say that risk is fanciful, I say: We know the Taliban supported al-Qa'ida; we know Iraq under Saddam gave haven to and supported terrorists; we know there are states in the Middle East now actively funding and helping people who regard it as God's will, in the act of suicide, to take as many innocent lives with them on their way to God's judgement.

Some of these states are desperately trying to acquire nuclear weapons. We know that companies and individuals with expertise sell it to the highest bidder and we know at least one state, North Korea, that lets its people starve while spending billions of dollars developing nuclear weapons and exporting the technology.

Can we be sure that terrorism and WMD will join together? If we are wrong, we will have destroyed a threat that, at its least is responsible for inhuman carnage and suffering. That is something I am confident history will forgive.

But if our critics are wrong and we do not act, then we will have hesitated in face of this menace, when we should have given leadership. That is something history will not forgive.

There is no more dangerous theory in international politics today than that we need to balance the power of America with other competitor powers, different poles around which nations gather.

Any alliance must start with America and Europe. Believe me if Europe and America are together, the others will work with us. But if we split, all the rest will play around, play us off and nothing but mischief will be the result of it.

We are part of Europe - and want to be. But we also want to be part of changing Europe. So don't give up on Europe. Work with it.

It is not the coalition that determines the mission but the mission, the coalition. But let us start preferring a coalition and acting alone if we have to; not the other way round. True, winning wars is not easier that way. But winning the peace is. And we have to win both.

We promised Iraq democratic government. We will deliver it. We will stay with these people until the job is done.

I want to be very plain. This terrorism will not be defeated without peace in the Middle East between Israel and Palestine. Here it is that the poison is incubated. Here it is that the extremist is able to confuse in the mind of a frighteningly large number of people, the case for a Palestinian state and the destruction of Israel; and to translate this into a battle between East and West; Muslim, Jew and Christian.

What the President is doing in the Middle East is tough but right. And why has a resolution of Palestine such a powerful appeal across the world? Because it embodies an even-handed approach to justice.

What [America] can bequeath to this anxious world is the light of liberty. That is what this struggle against terrorist groups or states is about.