President Clinton last night renewed his appeal to groups still involved in violence to stop and for the people as a whole to renew their efforts for peace.
In his address to a packed Market Square of Dundalk, President Clinton referred to the previous largest demonstration in the town when thousands of local people protested against the "Real" IRA's bombing of Omagh in August 1998.
Directing remarks at those still supporting violence President Clinton said: "You cannot win by making your neighbour lose."
Mr Clinton said: "Two years ago after the horrid bombing of Omagh you good people filled these streets. Young people came not wanting to lose their dreams. Older people came because they wanted a chance to live in peace before they rest in peace.
"You in Dundalk know what it is to face fear and isolation. We know violence suffocates opportunity.
"Fortunately the Irish had the opportunity to grasp the chance for peace and a new beginning. You stared violence in the face and said `No more'. You stood up for peace then and I ask you: stand up for peace today, tomorrow and the rest of your lives.
"There are still a few hills to climb on the road ahead but the people of Ireland have two advantages now. You now know the value of peace."
The US president praised the Republic's economic progress and said that "some of the smartest business people in the world" had shown their belief in the continuing peace and economic regeneration by investing here.
He specifically mentioned the £150 million Rank Xerox plant which has just opened in Dundalk and is already employing more than 800 in technology jobs. The president also praised the town's Institute of Technology, which has begun training courses aimed at the high tech industrial sector.
Also speaking in Dundalk last night the Taoiseach followed President Clinton's theme of denouncing violence and appealing for greater efforts for peace.
He said: "The people of Ireland treasure peace and, in every part of the island, totally reject that tiny minority who seek to destroy it. The Government will not swerve from doing all within our power to prevent all attacks on the people's right to peace."
Mr Ahern referred to the need for decommissioning, "totally and verifiably", and progress towards a "demilitarised society".
This was a reference to the Government's position on the need for a reduction in the number of British army observation posts, particularly along the south Armagh Border area.
There are about 30 posts and barracks in the Border area from Newry in Co Down to Co Tyrone. Several have been closed down but there is still a considerable military presence in south Armagh.
In his address to the people of Dundalk last night, Mr Ahern said: "More progress needs to be made towards a normal, demilitarised society, and weapons must be put totally and verifiably beyond use.
"The effective operation of the Good Friday institutions on a fully inclusive basis must be put beyond all doubt. There needs to be a police service in Northern Ireland which can attract full support of both communities."
He again paid tribute to President Clinton's role in helping the peace process in the North. He said: "It would not have been possible without you.
"You made clear that America was a friend of all who wanted peace and agreement. You showed everyone that you could be trusted not to promote a hidden agenda or yield to partisan pressures."
The Presidential visit to Dundalk was enveloped in a major security operation involving the US secret service, FBI and armed forces alongside the Garda and the Defence Forces.