US PRESIDENT Barack Obama has described Ireland's peace process as "blueprint" for the rest of the world to follow.
"Hope is contagious," he told a group of students in Belfast shortly after touching down on Irish soil.
The president received a rousing reception as he asked the group: "What's the craic?"
He spoke of how the peace process was an example for others to follow but he also joked about his love of golf and how he found his Irish ancestry.
"Our histories are bound by blood and belief and by culture and commerce.
"And our futures are equally inextricably linked. So that's why I come here today," he said.
Mr Obama recalled how his previous visit to Dublin was cut short by the Icelandic volcanic eruption, saying: "We've been eager for a chance to return to the Emerald Isle ever since."
But his main message was for the 2,000 young people in Belfast's Waterfront Convention Centre.
Noting that Northern Ireland has "unique challenges", he quoted WB Yeats saying "peace comes dropping slow".
"The terms of peace may be negotiated by political leaders but the fate of peace is up to all of us," he said.
"You should know that as long as you are moving forward, America will stand with you."
Mr Obama added: "A bullet need happen only once, but for peace to work we need to be reminded of its existence again and again and again.
"You must remind us of the existence of peace, the possibility of peace, you have to remind us of hope again and again and again."
He noted that there are still "peace walls" in Northern Ireland and it was up to the young people to take those down.
"THERE IS STILL MUCH WORK TO DO. THERE ARE WALLS THAT STILL STAND. THERE ARE STILL MANY MILES TO GO.
"From the start nobody was naive enough to believe that peace would be anything but a long journey.
"This work is as urgent now as it has even been. There is more to lose now than there has ever been."
He added that "peace is harder than war" but that he had "confidence" in the young people of Ireland to "embrace that path".
"The United States of America will support you every step of the way," he said.
On a lighter note, the president fondly recalled his short visit to Dublin in 2011 when he addressed tens of thousands of people in College Green and travelled to his ancestral home in Moneygall.
He laughed that he had no doubt that Henry Healy was his cousin after meeting him.
"I knew he was cousin because his ears flapped out just like mine," he said.
Explaining how "it pays to be Irish in Chicago", he recalled how he proudly watched as "Michelle learn to pull a pint of black".
And he told how local hero Rory McIlroy had promised to help him sort his golf swing out.
But he added that unfortunately he won't be able to sneak in a few rounds during the G8 summit.
Tensions over Syria look set to dominate the G8 summit as Mr Obama is joined by world leaders in Co Fermanagh.