From UN Secretary General Kofi Annan's speech at the 57^th session of the General Assembly:

The terrorist attacks of that day were not an isolated event. They were an extreme example of a global scourge, which requires a broad, sustained and global response.

Broad, because terrorism can be defeated only if all nations unite against it.

Sustained, because the battle against terrorism will not be won easily, or overnight. It requires patience and persistence.

And global, because terrorism is a widespread and complex phenomenon, with many deep roots and exacerbating factors.

Mr. President, I believe that such a response can only succeed if we make full use of multilateral institutions.

I stand before you today as a multilateralist – by precedent, by principle, by Charter and by duty.

I also believe that every government that is committed to the rule of law at home, must be committed also to the rule of law abroad. All States have a clear interest, as well as a clear responsibility, to uphold international law and maintain international order.

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On almost no item on our agenda does anyone seriously contend that each nation, or any nation, can fend for itself. Even the most powerful countries know that they need to work with others, in multilateral institutions, to achieve their aims.

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Any State, if attacked, retains the inherent right of self-defence under Article 51 of the Charter. But beyond that, when States decide to use force to deal with broader threats to international peace and security, there is no substitute for the unique legitimacy provided by the United Nations.