LONDON - He didn't care much for foreign policy matters and didn't mind that people noticed his lack of interest. But with only nine months remaining to the end of his presidency, Mr Barack Obama is now busily recasting himself as an international relations guru.
The US President now gives long interviews on foreign matters to scholarly magazines read by the sort of policy wonks he never welcomed to his White House.
Mr Obama has also just concluded a week-long jaunt to Europe, which proved short on real work but rich in photo opportunities. Similar grand tours are being planned for Asia in the near future.
One explanation for this remarkable transformation is the traditional desire of any US president to leave a positive legacy. But another reason for Mr Obama's increasingly frantic efforts to explain his approach to the world is the near-certainty that foreign policy would be remembered as the most controversial aspect of his presidency.
For what is increasingly being referred to as the "Obama Doctrine" not only diminished America's global footprint but is now also restricting the foreign policy options available to Mr Obama's successors.
The foreign policy straitjacket under which Mrs Hillary Clinton now has to operate and the intellectual void in which Mr Donald Trump floats are both the result of fundamental flaws in Mr Obama's foreign policy vision.
Any president who came after Mr George W. Bush was bound to be more cautious in the use of American power.
By the time Mr Obama walked into the Oval Office, the United States had spent almost a decade fighting wars it could not win; ordinary Americans were emotionally exhausted and spooked by the global financial crisis.
Mr Obama therefore enjoyed broad public support for his decision to withdraw US troops from Afghanistan and Iraq, and for his subsequent refusal to consider the use of force as America's knee-jerk response to any crisis.
Mr Obama was also right to question the idea that each major conflict required US involvement, or that each crisis had a solution invented in Washington.
As Johns Hopkins University foreign policy professor Michael Mandelbaum put it in a book which provided an intellectual coherence to Mr Obama's stance, the US walked from one foreign policy failure to another because it allowed itself to "be concerned with the internal politics and economics rather than the external behaviour of other countries".
But Mr Obama was wrong to assume that his bias against the use of force imposed no long-term consequences on America's global stance and influence. The President continues to claim to this day that "America remains the world's indispensable power", while at the same time making no secret of his preoccupation with making this indispensability less expensive.
The President has also surrounded himself with top security advisers who believe that the US has a moral and even legal obligation to use its power to right wrongs around the world; Ms Samantha Power, the current US Ambassador to the United Nations, is the author of a celebrated book criticising previous American administrations for failing in their "responsibility to protect" other nations from their own murderous leaders.
But when his advisers suggested - as they have done repeatedly over the war in Syria - that the time may have arrived for the US to deploy its firepower, the President simply brushed them away.
"Obama generally does not believe a president should place American soldiers at greater risk" - concluded Mr Jeffrey Goldberg, the journalist who completed a recent 40-page interview with him for The Atlantic magazine in the US - unless the crises in question "pose a direct security threat to the United States".
Again, a perfectly understandable position but one which is also deeply unsettling to America's allies.
For the US President has never offered a workable definition of what would represent a fundamental challenge to the US necessitating the use of force.
The 2014 Russian invasion of Ukraine was breezily dismissed by Mr Obama as no such direct threat, notwithstanding the reality that this was the first time since World War II when one European country annexed the territory of another in Europe. China's behaviour in the South China Sea is also no direct threat to the US.
Neither, apparently, is North Korea's nuclear quest.
And Syria was also not considered worthy of US military intervention despite the fact that the President himself once solemnly declared that "when hundreds of innocent children are killed" in that conflict "and there is no action, then we're sending a signal that international norm doesn't mean much, and that is a danger to our national security". Since then, almost half a million Syrian civilians perished, but none warranted US intervention.
Given such a record, America's allies are entitled to wonder whether the security guarantees they currently enjoy will ever be redeemed in times of crisis. But instead of dispelling such worries, Mr Obama simply brands them irrational.
One of the most enduring characteristics of the current administration is its habit of being dismissive of allies while extending great courtesies to enemies: the Europeans are publicly criticised as "free riders", Arab monarchies are told that their biggest threat comes from their own people, but when Iran's leaders machine-gun domestic demonstrators or seize US sailors on the high seas, Washington congratulates itself on maintaining its official silence.
And notwithstanding his phenomenal intellect, Mr Obama simply refuses to accept that, when he retreated from his famous "red line" over the use of chemical weapons in Syria, that damaged the reputation of the US. The President rejects the argument that every threat to use force has to be backed by the actual use of force; he ridicules this as "dropping bombs on someone to prove that you're willing to drop bombs on someone".
Yet although that's a clever line, it's also beside the point: the fact remains that, when the US leader explicitly threatens to use force but then fails to follow this through, that emboldens America's opponents.
Russian President Vladimir Putin decided to send his troops to Syria precisely because he perceived Mr Obama to be weak. The result is that decades of US supremacy in the Middle East is now at risk; neither the Middle East nor the US is better off as a result.
But arguably the most significant impact of the Obama Doctrine has been to restrict and impoverish the debate about foreign policy among his successors during the current presidential electoral campaign.
Mr Obama, of course, cannot be held accountable for the emergence of Mr Donald Trump; the property tycoon is an accident, rather than a product of American democracy.
But although Mr Trump's foreign policy strategy is just a mixture of cliches and banalities best ignored, many of the assumptions which the Republican aspirant is making are tacitly shared by other US presidential candidates.
All presidential candidates seem to take the current international system for granted, and all assume that it's up to the US to decide how much or how little it wishes to become engaged in it.
All appear to suggest that most international conflicts should just be allowed to burn themselves out, regardless of how heavy the carnage may be.
And all candidates demand that "others" do more to protect themselves, rather than expect Washington to do so.
The idea that the international system as it exists today actually serves American purposes, and that the US gets the best results from its allies when it leads by example rather than berating them in public seems to have disappeared from the current electoral discussion.
And much of the blame for this lies with the Obama Doctrine and its shortcomings.
Although she won't admit it publicly, Mrs Clinton is painfully aware that one of her first tasks upon winning the White House will be to discard the doctrine of her predecessor.
The question is whether, given the current state of the debate on the matter, she can win the support of Congress and public opinion to a more assertive US policy.
Mr Obama is fond of saying that, just because the US has a military considered as the world's "best hammer", this "doesn't mean every problem is a nail".
True, but if a future US president persists in refusing to notice any nails, she or he should not be surprised if others begin to wonder whether the leader of the world's only superpower has simply forgotten how to wield a hammer.
This article was first published on May 2, 2016.
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