A popular American bumper sticker from the later Bush years featured the words "Endless War" altered by a handwritten scrawl to read "End This War".

That sentiment, of course, was directed at a president and vice-president who seemed to see the military as the solution to most problems, to believe perpetual combat would promote their theories of strong executive-centred government and to hope these together would secure permanent control of the White House and Congress for the Republican Party.

All of this was worth reflecting on last week as Barack Obama travelled to Oslo to pick up his Nobel Peace Prize even as his defence secretary, Robert Gates, made what proved to be an unusually awkward trip to America's two war zones: Iraq and Afghanistan.

In Oslo, Obama (not for the last time, one suspects) both acknowledged and worked to reconcile the contradictions of his many roles. "I come here," he said, "with an acute sense of the costs of armed conflict filled with difficult questions about the relationship between war and peace, and our efforts to replace one with the other."

He sought to justify Afghanistan as a war that must be fought while reminding his audience that Iraq is a war he would not have sought, and one that he is moving to wind down. An odd sign that things are getting better in Iraq came last Thursday when Gates, visiting Baghdad, was stood-up by Prime Minister Nouri Al Maliki.

Al Maliki was at the Iraqi parliament, defending his own security record in the wake of a bloody series of bomb attacks. He sent word to Gates that parliamentary duties left him too busy to see the American defence secretary (the meeting was eventually rescheduled for the following day).

Compare this with 2006, when Al Maliki was not even told of a Baghdad visit by President Bush until a few minutes before he was ushered into the American leader's presence. Or 2007 and 2008, when Washington openly discussed whether the time had come to replace the democratically-elected Iraqi prime minister.

However, one may feel about Al Maliki, this incident says something about how he views his own political position. With an election coming up in a few months, publicly snubbing Gates is a convenient way to display independence to Iraqi voters. That is a sign of progress. An Iraq where leading politicians are more scared of their constituents than they are of visiting American bigwigs is an Iraq that has come very far indeed.

Gates, at least, could take some solace in the fact that the Baghdad snub had few domestic political implications for him. Nothing about it was nearly as problematic as Afghan President Hamid Karzai's unexpected comment during a joint news conference that his country won't be able to foot the bill for its own army until 2024. That remark is certain to follow Gates to a series of Congressional hearings this week where he has the unenviable task of securing funding for the Afghanistan troop surge Obama announced earlier this month.

Unlike his predecessor, Obama avoids referring to himself as a ‘war president'. In his Nobel lecture he addressed the philosophical concept of Just War and spoke of the need to confront evil. But he also acknowledged "these two seemingly irreconcilable truths — that war is sometimes necessary, and that war at some level is an expression of human folly."

Bill Clinton knew that presidents become great only when they rise to the challenge of titanic events, and is said to have lamented that history never presented him with such a moment.

Confronted with a historic challenge in the early months of his presidency, George W. Bush initially rose to the occasion, but then cheapened the tragedy of 9/11 by claiming it as a justification for every action, foreign or domestic, that he took over the next seven years.

Obama's message in Oslo seemed to be that each of the wars he has inherited must be wound down in the way least likely to make things worse. This will involve protecting America's security and rebuilding its global reputation while working mightily not to leave a vacuum behind when it, finally, leaves. Achieving all that may prove to be a challenge as great, in its own way, as 9/11 itself.

Gordon Robison, a writer and commentator who has lived in and reported on the Middle East for two decades, teaches political science at the University of Vermont.