It's hard to imagine a successor so at odds with Obama's view of the world
Eight years ago this week, I joined the massive crowds - some estimates put the number at almost two million - that flocked to Washington DC for Barack Obama's inauguration.
Hundreds of thousands stood on the Mall for hours in the biting cold waiting to hear Mr Obama speak for the first time as president. When he did, a hush descended. Such was the solemnity of the occasion, the realisation that history was being made with the first black president of the United States, that only a few times was his address interrupted by applause.
Two are lodged in my memory: when Mr Obama rejected what he painted as a false choice "between our safety and our ideals" and when he sent a pointed message to adversaries that America would "extend a hand if you are willing to unclench your fist". Many took those lines, in addition to his references to the need for mutual respect, humility and restraint, as hints on how US foreign policy would unfold under an Obama administration.
Within a couple of months, I witnessed how the powerful symbolism of Mr Obama's presidency had reached some of the most remote corners of the world. In a market in a small town in eastern Chad, a trader approached me pointing to his own face. He wanted to express his delight that the president of the United States was now a man who, as he put it, "looks like me".
Two presidential terms later, as the world holds its breath to see what a Donald Trump presidency might bring, Mr Obama's vision of an "interdependent" world, a world of co-operation which transcends not just physical borders but also those imposed by conflict and mistrust, appears to be in retreat.
The high expectations of how Mr Obama might shape the world are a distant memory now. His stirring speeches to Europeans in Berlin shortly before his election and to Muslims in Cairo months after his inauguration raised hopes, but his premature Nobel Peace Prize less than a year into his presidency was rightly criticised at the time.
In the end, his foreign policy successes were few. The deal with Iran, aimed at preventing Tehran from developing nuclear weapons but also ending the chill in relations between the two countries, was the most notable, followed by the Paris climate change agreement and the historic rapprochement with Cuba. All three may now be at risk during the Trump presidency.
Over the last eight years, I have seen the impact of Mr Obama's foreign policy decisions up close in several parts of the world. In Pakistan, people told me of their anger and resentment over the civilian deaths caused by his drone war on the restive border region with Afghanistan. In Pakistan, Somalia and Yemen, Mr Obama dramatically expanded the US drone programme, carrying out 10 times more strikes than his predecessor George W Bush.
For the last five years I have reported on Libya, from the 2011 Nato-led intervention that helped bring an end to Muammar Gaddafi's 42-year-old regime to the instability that has plagued the country since as it struggled to transform itself from dictatorship to democracy. Mr Obama has spoken often of his regrets over Libya. The biggest mistake of his presidency, he said last year, was "probably failing to plan for the day after what I think was the right thing to do in intervening in Libya".
Many Libyans would agree. They say they feel let down by the Western powers that helped them dislodge Gaddafi, though after his overthrow Libyans refused further assistance, insisting they could handle the aftermath themselves.
What happened in Libya in turn affected Mr Obama's calculations on Syria and his eventual conclusion that while the threat posed by the expansion of Isil there required a military response, the ruthless war of the Assad regime against its own people did not.
In his last press conference as president, Mr Obama justified his much-criticised Syria policy as being underpinned by what he said was a sense of "what's the right thing to do for America". History will be the judge of that, as the grim fallout from Syria's horrific conflict promises to continue making itself felt far beyond its borders for years to come. As a Syrian refugee in Europe put it to me last year: "We are seeing the bitter harvest of ruined hopes."
Mr Obama's blotted foreign policy record aside, it is almost impossible to imagine a successor so at odds with his view of the world as Trump. While the shape of the mercurial Mr Trump's policies remain to be seen, his strident economic nationalism, his opposition to what he derides as "globalism", his disdain for long-standing alliances like Nato and hostility towards immigrants and Muslims do not bode well.
Mr Trump's approach to the world is more transactional than visionary. The Obama era is over in more ways than one.