If the United States is at war, as was stated yesterday by President Bush and the Secretary of State, Mr Colin Powell following Tuesday's mass atrocities in New York and Washington, it matters greatly who is its enemy and how the war is going to be fought. Yesterday saw the emergence of some hard evidence about those responsible and how US friends and allies will respond, as the huge and shocking extent of the thousands of deaths and the devastation sank in.
Many Irish-Americans are, sadly, among the victims of what President McAleese has aptly described as "a crime against the foundations of our common humanity". She went on to say "we must stand shoulder to shoulder" with the United States at this time - a statement that accurately reflects popular feeling in this country, which has so many human contacts there. The Taoiseach's announcement of a national day of mourning tomorrow expresses that solidarity very well.
Mr Powell vowed to act swiftly and firmly against those found to be responsible for the attacks and to mobilise the rest of the world in support. The administration is under growing popular pressure to take rapid action. But in deciding when and how to do so it must also remember not to let those who used terror against the world's greatest democracy to set an agenda that would weaken its structures of freedom and law. They would achieve that if the US lashes out emotionally against an ill-defined foe rather than awaiting clear evidence and creating an international consensus for punitive action.
Holding that balance between emotion and reasoned determination will be a crucial test of President Bush's leadership and administration. Yesterday's apparent progress by police in tracing some of those responsible in Boston and Florida is a hopeful sign that they can be accurately identified, along with the international terrorist network of which they are part.
Equally significant was the announcement by the NATO Council in Brussels that they are prepared to invoke Article 5 of its founding treaty for the first time in its history to declare that the New York and Washington atrocities are an attack on one and all in the alliance. This would commit each member-state "to take such action as it deems necessary, including the use of armed force, to restore the security of the North Atlantic area". This is a strong political gesture of international solidarity for the US government, although it would not automatically lead to the use of force. It is explicitly related in the text of that clause to the United Nations Security Council's role "to restore and maintain international peace and security".
Such prompt international support, along with that expressed by the European Union and other states yesterday, holds out the hope that the US government will act together with others in seeking out and punishing those responsible for the atrocities, rather than striking out on its own against them without preparing its right to self-defence fully and deliberately. Any effective campaign against international terrorism will have to tackle its root causes as well as the transient and suicidal individuals who carry out such outrages.