By Martina Purdy
BBC NI political correspondent
George and Laura Bush have a number of engagements in Northern Ireland
There will be something of a race across the Irish Sea between George Bush and Gordon Brown.
That is because the prime minister will be bidding farewell to the US president in London - and then has to be at Stormont before him to say hello again.
So if Air Force One is circling above the airport, it's because the prime minister's aircraft is lagging behind.
The rush is something of a metaphor for this visit.
George Bush will be in Northern Ireland for the afternoon, along with the first lady.
It's a low-key affair compared to the crowd-pleasing visits by Bill and Hillary Clinton.
Bill Clinton likes to point out he was the first sitting president to visit Northern Ireland.
And his presidential visits, three in all, were often used to inject some hope into a rather imperfect peace.
Mr Clinton first came to Belfast in 1995, memorable because of his handshake with Sinn Fein leader Gerry Adams on the Falls Road.
Van Morrison played a concert outside Belfast City Hall, when the president turned on the Christmas lights.
Mr Clinton returned in September 1998 to celebrate the Good Friday Agreement.
But his visit so soon after the devastating Omagh bomb and the murder of the Quinn children was seen as a way of injecting hope amid despair.
His last visit here was more a lap of honour, but he used the occasion to encourage the parties to resolve the outstanding issues.
George Bush, by comparison, is not looking to soak up any comfort from adoring crowds, and he is not in Northern Ireland to fix a crisis.
Rather his visit, largely a political favour, will be short - long enough to say hello - and remind Americans back home that Northern Ireland is now stable and at peace.
His trip will also be marked by protest, just as his previous one was in April 2003.
Bill Clinton and Tony Blair pictured on a walkabout in Belfast in 1998
He came to Hillsborough Castle amid angry demonstrations over the invasion of Iraq.
That visit was a favour to Tony Blair.
The pair met at Hillsborough where the president greeted the politicians who were trying to break one of the many Ulster Unionist/Sinn Fein deadlocks. The protestors were kept well away from the Castle.
Among those protesting this time will be Ogra Shinn Féin.
While Martin McGuinness smiles at George Bush, his party's youth wing will be protesting "visibly and vocally" against the "US occupations of Iraq and Afghanistan".
The first lady will be staying away from Stormont. Instead, Laura Bush will greet schoolchildren in Belfast. The president is also due to visit a school.
As for Taoiseach Brian Cowen, he will also come to Stormont for his meeting with the US president.
But there will be no photocall at Parliament Buildings, and the assembly members will not be gathering in knots to say hello either.
Bill Clinton famously shook hands with Gerry Adams on the Falls Road in 1995
The Stormont sitting is cancelled nonetheless, a point of contention for the Alliance Party.
MLA Kieran McCarthy has complained the decision to cancel by the DUP and Sinn Féin is a "joke."
"The DUP and Sinn Féin would do better to get down to some work on Monday instead of glad-handing with President Bush," he said.
The Bush visit will have one thing in common with Clinton's: security will be tight and traffic will come to a standstill in some parts of the city.