President Bush has promised the British people that democracy will prevail in Iraq and advance his "forward strategy for freedom" and peace in the greater Middle East.
In the keynote speech of his three-day state visit to Britain, the president assured an invited audience at London's Banqueting House there would be no American "retreat" from Iraq.
"We did not charge hundreds of miles into the heart of Iraq and pay a bitter cost of casualties and liberate 25 million people, only to retreat before a band of thugs and assassins," he declared. "We will help the Iraqi people establish a peaceful and democratic country in the heart of the Middle East and by doing so, we will defend our people from danger."
Amid pomp and ceremony at Buckingham Palace and anti-war protests on the streets, President Bush had travelled to Whitehall to celebrate the "special relationship" between the two countries and describe Britain as America's "closest friend in the world".
He plainly delighted the British Prime Minister, Mr Tony Blair, with a wide-ranging speech in which he praised NATO as "the most effective multilateral institution in history"; affirmed his support for the United Nations, whose credibility depended "on a willingness to keep its word and to act when action is required"; directed equally tough messages to both sides in the Arab-Israeli conflict, and dismissed the idea "that Islam is somehow inconsistent with a democratic culture".
Praising the speech, Mr Blair's official spokesman commented: "We've said people should listen to the president rather than respond to a caricature. What we had was a coherent world vision."
The Middle East loomed large in that vision, President Bush told his audience: "By advancing freedom in the greater Middle East, we help end a cycle of dictatorship and radicalism that brings millions of people to misery and brings danger to our own people."
The president continued: "The stakes . . . could not be higher. If the Middle East remains a place where freedom does not flourish, it will remain a place of stagnation and anger and violence for export. And as we saw in the [September 11th\] ruins of the two towers, no distance on the map will protect our lives and way of life.
"If the greater Middle East joins the democratic revolution that has reached much of the world, the lives of millions in that region will be bettered and a trend of conflict and fear will be ended at its source."
Achieving peace in the Holy Land was not just a matter of the shape of a border, Mr Bush said. "As we work on the details of peace, we must look to the heart of the matter, which is the need for a viable Palestinian democracy."
Peace, he said, would not be achieved "by Palestinian rulers who intimidate opposition, who tolerate and profit from corruption and maintain their ties to terrorist groups."
These were the methods of "old elites" who put their own self-interest above the people they claimed to serve. "The long-suffering Palestinian people deserve better," insisted President Bush. "They deserve true leaders, capable of creating and governing a Palestinian state."
Stressing his equal commitment to security and recognition for the State of Israel, President Bush said: "Israel should freeze settlement construction, dismantle unauthorised outposts, end the daily humiliation of the Palestinian people and not prejudice final negotiations with the placements of walls and fences."
While some commentators thought these the harshest words yet directed by the president toward the Israelis, the view in Whitehall last night was that it was "a case of balanced messages for both sides" - which one senior official suggested might actually owe something to the lessons drawn by the US administration from the British experience of the peace process in Northern Ireland.
Mr Blair does believe the peace process there provides a template for conflict resolution around the globe.
Yesterday President Bush's template was in the form of "three pillars" involving international organisations "equal to the challenges facing our world"; the willingness of free nations to use force in the last resort to resist tyranny and the spread of democracy across the world.
However the over-arching and recurring theme of the president's address was the new terrorist threat of the 21st century - what he called "the evil in clear sight".
The last American President to stay at Buckingham Palace Woodrow Wilson, had vowed in the presence of King George VI in 1918 that "right and justice would become the predominant and controlling force in the world".
Yet at Wilson's high point of idealism, "Europe was one short generation away from Munich and Auschwitz and the Blitz".
Recalling the failure of the then League of Nations "at the first challenge of the dictators", President Bush said: "Through world war and cold war, we learned that idealism, if it is to do any good in this world, requires common purpose and national strength, moral courage and patience in difficult tasks. And now our generation has need of these qualities."
Mr Bush continued: "On September 11th, 2001, terrorists left their mark of murder on my country and took the lives of 67 British citizens. With the passing of the months and years, it is our natural human desire to resume a quiet life and put that day behind us, as if waking from a dark dream."
But he warned: "The hope that danger has passed is comforting, is understandable and it is false."
Citing ongoing terror attacks around the world, he said: "These terrorists target the innocent and they kill by the thousands. And they would, if they gain the weapons they seek, kill by the millions and not be finished.
"The greatest threat to our age is nuclear, chemical or biological weapons in the hands of terrorists and the dictators who aid them. The evil is in plain sight. The danger only increases with denial. We will face these threats with open eyes and we will defeat them."