By Paul Reynolds
World Affairs Correspondent, BBC News website
Tony Blair's visit to Washington was a sunset moment. He and George Bush are coming to an end of their time together.
Blair and Bush still face possible future crises
This does not necessarily mean an end to their crises together, because one potentially huge problem, Iran, is yet to be dealt with.
Not that they were able to sit back and relax in a golden glow over the Potomac River. There were too many shadows.
Both found themselves having to make apologies over Iraq (tactical not strategic), especially Mr Bush as it turned out.
Tony Blair was more interested in determinedly trying to lay out his international legacy, a philosophy of interventionism in which Iraq found its place.
In a speech in the calm surroundings of Georgetown University, Bill Clinton's old haunt, he urged support for the new government of Iraq to mark a break with "old arguments" about the invasion.
At some stage, the US will have to decide whether it intends to attack Iran's nuclear facilities if there is no previous diplomatic agreement
A "new concordance" should replace the "old contention".
That has to be a bit optimistic.
After all, it is partly his role in Iraq that has led to the undermining of his own domestic position.
To expect people to rally round the Iraqi government is one thing. To expect them to rally round him as well is surely another.
Ideas and issues
He did call for a series of quite bold moves internationally, though it is unrealistic to expect many of them to be implemented.
They included another call for more permanent members of the United Nations Security Council (Germany, Japan, India and states from South America and Africa); for greater powers for the UN secretary general; for a UN environment agency; for reforms to the IMF and World Bank and an expansion of the G8 group of industrial countries to take in five more members.
Will the next British leader be as keen on US undertakings?
He also floated the intriguing idea of the UN's nuclear agency, the International Atomic Energy Agency, overseeing the development of the international enrichment of uranium.
This is presumably seen as a way of avoiding another crisis like the other over Iran.
But it was just one in a fairly long list of ideas and was not developed. Maybe it will be.
Taken together, he did offer at least an attempt to describe a philosophy of interventions by the UN and in which Iraq, the "child of democracy" as he put it, found its place.
But the critics will also argue that it was the war in Iraq, declared as "illegal" by the UN secretary general himself, which did the major damage to the UN ideals and that it is now too late to square that circle.
Nevertheless, he did raise issues that the world must contemplate in the forthcoming post Bush/Blair era.
Will the United States draw in its horns under the next presidency (still two and a half years away, incidentally)?
Will the next British leader be less ready to join in American undertakings?
Will the UN re-establish its credibility?
As mentioned earlier, the looming crisis is over Iran.
At some stage, the US will have to decide whether it intends to attack Iran's nuclear facilities if there is no previous diplomatic agreement and no such agreement appears likely.
Mr Blair no longer has a foreign secretary who is clearly against any military action and he himself has simply said that it is sending the "wrong signal" to Iran to rule out any option.
That does not mean he would favour such action or take part in it.
But it leaves a little door open to the prospect of seeing Messrs Bush and Blair back together in an international crisis, though whether with the same policies remains to be seen.
The sun may be going down but it has not quite gone yet.