A minute of silence to mark a world of mourning
In a gesture of support and solidarity, schools, shops and businesses here will come to a symbolic halt at 1.46pm the precise moment, Irish time, that the first terrorist hijacked plane hit the North Tower of the World Trade Center in New York exactly one year ago.
Across the world, airlines, embassies, major financial centres, Western military bases and American-owned companies are on high alert for fear of a repeat attack on the first anniversary of the atrocities.
But as extra police and security forces step up the pace of already intensive surveillance, political leaders are urging communities to take time out to reflect on the events that reduced the world's most powerful nation to tears and which have dominated international relations ever since.
In the US, President George Bush will make a pilgrimage from the Pentagon to the Pennsylvania field where one of the four hijacked planes crashed, and then on to Ground Zero in New York where the World Trade Center once stood. He will later address the American people from Ellis Island in New York harbour, in the highly symbolic shadow of the highly symbolic Statue of Liberty.
Here, business in Leinster House will be suspended as the Dáil and all government departments observe the minute's stoppage in solidarity with the bereaved relatives of the more than 3,000 people who died.
The Taoiseach has asked that members of the public and essential service providers who cannot participate take a personal moment to reflection later in the day.
Mr Ahern, the Tánaiste and other senior political and political and public figures will attend a series of religious and other commemorative events throughout the day beginning with a special Mass in St Mary's Pro Cathedral in Dublin at 11am.
Firefighters and the Garda Commissioner will also be there to pay tribute to their fallen comrades in the New York rescue services who lost their lives trying to save those trapped in the Twin Towers.
At 1pm, members of the Dublin Fire Brigade will lay a wreath at a private commemoration service at the American Embassy which the Taoiseach will also attend. President Mary McAleese will be represented at both events by her aide de camp.
Mrs McAleese, who is in Co Fermanagh on a series of engagements, will observe the minute's silence at a Rotary Club lunch in Enniskillen.
In a special anniversary message, Mrs McAleese said the passage of time had not lessened the "enduring,shocking images of the cruel atrocities which were visited on the United States".
"At the root of those dreadful events in New York, Washington and Pennsylvania was mankind's most potent weapon, hatred. Its causes are complex, its effects catastrophic, as we in Ireland know only too well," she said.
"Humankind owes it to those who died on September 11 and to all whose lives are blighted by hatred to redouble our efforts to promote a truly effective, communicating global environment in which festering bitterness and distrust give way to love and respect for every human being."
Cardinal Connell will remember the victims in prayers when he celebrates International Mass in Lourdes where he is leading the Dublin Diocese annual pilgrimage.
While today's events will focus on the horrors of a year ago, much attention will also be on the unfolding plans for the next phase of the still developing drama.
The Minster for Foreign Affairs, Brian Cowen, flew to New York last night and will represent the Government at commemorative events today but he is also in the city to attend the current session of the United Nations General Assembly.
President Bush is scheduled to address the Assembly on Thursday when he is expected to give further indications of his plans for tackling Iraq, the next country on his "axis of evil" list.
Mr Cowen will address the Assembly on Friday, but despite calls from opposition parties here to make clear Ireland's opposition to any non-UN sanctioned offensive against Iraq, it is not clear whether he will raise the issue.
Back home, Garda and Department of Foreign Affairs spokesmen would not detail security arrangements for the anniversary but said all necessary measures would be taken.
No noticeable fall-off in air travellers has been recorded from Irish airports and Aer Rianta said security at all airports had been enhanced since September 11 last year and continued to be so.



