In a remarkable confluence of events President Bush and Mr Tony Blair began their summit in Northern Ireland last night on the very day it became clear that the war in Iraq is probably coming to a relatively speedy end.
Reports from Baghdad and Basra indicate mainstream Iraqi military resistance to the US-British invasion force is collapsing after the lethal battles of recent days.
This makes the agenda of the Hillsborough Castle talks all the more pressing - crucial indeed for the shape of post-war Iraq, how the United Nations will be involved in it and for the Middle East peace process with which the Iraq war is intimately connected. Mr Blair's political gamble on influencing the Bush administration will be put to a major test in the outcome of this meeting.
The sheer professional and technical superiority of the US-British military forces has told hugely in the last week of fighting for Baghdad and Basra. It shows in the devastation their armoured and airborne weaponry has inflicted on Iraqi forces drawn into open conflict with them. That has given the invading forces more confidence to penetrate to the heart of these cities - despite the shocking toll of civilian and military casualties.
It appears that the urban guerrilla fighting predicted to follow will not materialise on the large scale that was widely anticipated - although it is too early to say this with certainty. If it proves true there could be still continuing resistance after Baghdad falls, but without the mass threat to civilians such a prolonged battle would involve.
Although this war was mounted unacceptably without explicit UN Security Council approval, all concerned will be hopeful that it now looks more likely to be concluded sooner rather than later. Today's discussions between Mr Bush and Mr Blair will tackle the UN's role in post-war Iraq and how the crisis there is related to the Israel-Palestinian peace process.
Unless the UN has a central role in endorsing the government of Iraq, as well as in reconstruction and humanitarian aid, the war's outcome will lack international legitimacy and reflect only the interests of those who successfully prosecuted it. Arguments within the Bush administration are still raging on this subject. Mr Blair is also pressing Mr Bush to publish the agreed road map on an Israel-Palestinian settlement.
The Taoiseach, Mr Ahern, will support Mr Blair's arguments on both issues at today's summit. They deserve the most careful hearing by Mr Bush, who will benefit from the political kudos of being associated with historic developments in the Northern Ireland peace process later this week.