BBC Washington bureau staff have been reporting the news of Barack Obama's first year in office day in day out since 20 January 2009. On the anniversary of his inauguration, they sum up some of the key developments.
MICHELLE FLEURY: ECONOMY
The month before Barack Obama took office, the US economy lost more than half a million jobs, 300,000 homes were being foreclosed and the survival of the US banking system was in doubt.
A year later it is fair to say the big picture is a lot rosier. Financial markets have rallied strongly during Mr Obama's time in office and the biggest banks, at least, have returned to some semblance of stability.
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But for many millions of Americans, the Obama presidency has, so far, been a time of declining fortune. The rate of job losses has slowed from the terrifying days of winter 2008/9, but it has not reversed. The unemployment rate sits at 10%.
The stimulus package of last year certainly created some jobs. But how many and for how long is yet another subject of intense political debate.
In political terms, the economy is now a real problem for President Obama. He faces the prospect of having to argue that however bad things are for many voters, without him, they would be even worse. That is always a difficult case to make.
KEVIN CONNOLLY: HEALTHCARE
Politically, Barack Obama had all the cards needed to make healthcare reform happen - a strong mandate for a policy he talked about during the campaign, and Democratic majorities in the House and the Senate.
Still, things did not go smoothly. Several self-imposed deadlines were missed, and President Obama never produced his own clear blueprint for change.
That left the House and Senate each to produce their own versions and messy haggling is now needed to reconcile them.
There will not be a government-run scheme - a disappointment to the left.
But two big problems will be solved. About 30 million Americans who currently do not have insurance will get it. And insurance companies will not be able to refuse cover to people who are sick, as they can now.
The politics have been inelegant - but President Obama is on the brink of a major achievement, removing a nightmare of insecurity from millions of American lives. There is still a risk though that voters could punish Democrats in the mid-term elections in November, for the higher tax bills that will pay for change.
ADAM BROOKES: GUANTANAMO
It was one of the president's first acts - the issuing of orders to close the Guantanamo Bay detention camps and the secret CIA-administered prisons, and to renounce torture.
One year on, the Guantanamo Bay camps remain open, and 200 or so inmates remain within their walls. A one-year deadline for closure will be missed. The administration says it has plans to release some detainees, and to try others. It seems all but certain, though, that a small group of inmates will continue to be held without trial.
Hundreds more are held without trial at Bagram, in Afghanistan. Bagram is not Guantanamo - it is deemed to be on a battlefield, so different rules apply. But it, and detention without trial, will dog President Obama's presidency.
On "enhanced interrogation", which some have called torture, occasional accusations of abuse have surfaced through the year, but the line drawn by Mr Obama seems to have held.
In one area, civil rights groups remain concerned. The president has made clear he does not wish to see the prosecution of military and intelligence officers who used "enhanced interrogation techniques" in recent years.
But overall, the president has had success in changing the language and tone of detention and national security policy. His Nobel Peace Prize - for a wartime president, no less - is evidence of that.
PAUL ADAMS: CLIMATE
Barack Obama's views on climate change mark a radical change from the Bush era. The president personally attended the UN climate change summit in Copenhagen in December - and he went there saying he wanted to lead.
The summit failed to produce an all-encompassing deal, but the president and the Chinese premier, Wen Jiabao, did broker a political deal that bound the world's two largest emitters together for the first time.
Mr Obama admitted it was "not enough", and it seems clear he intends to lend what support he can to a broader agreement.
He faces a domestic fight. The House of Representatives passed legislation in the summer, including a 17% reduction in CO2 emissions by 2020, based on 2005 levels.
But the Senate has yet to debate the issue. With healthcare reform - the president's top domestic priority - yet to be passed, some Senate Democrats are urging him not to take on another politically toxic issue at the start of a mid-term election year.
The administration could have to settle for another strategy - using the Environmental Protection Agency to start limiting emissions with or without new legislation from Congress.
KIM GHATTAS: AFGHANISTAN
President Obama's name is now all over the war in Afghanistan, and the situation there three years from now will play a big part in determining how his presidency is eventually remembered.
Much to the dismay of anti-war activists, Mr Obama is sending an additional 30,000 troops to Afghanistan.
But the Nobel Peace Prize winner seemed to do that hesitantly, drawing criticism from Republicans.
Obama's Afghanistan and Pakistan policy reflects his general approach to foreign policy - a comprehensive, regional look at all the layers of a problem - in this case, one allowed to fester under the Bush administration.
Obama has put in place a civilian strategy, key to building up the Afghan state and diminishing the appeal of radicalism.
He has also finally convinced Nato to contribute more troops.
At the same time, this US administration is working hard to persuade Pakistan to clamp down on al-Qaeda and the Taliban. But Islamabad will only act in earnest if there is progress on the Kashmir front - and that is one issue Washington does not seem able or willing to tackle.
VANESSA BUSCHSCHLUTER: POLLS
Barack Obama has had to make the transition from the poetry of campaigning to the prose of governing - and his poll ratings have slid dramatically during the past year.
On 16 January 2010, only 50% of Americans approved of his job performance, down 18% from the day of his inauguration, according to a Gallup poll.
A decline of this size in the first year is unusual, but a 50% approval rating after 12 months is not unheard of. Ronald Reagan's ratings were equally low after his first year in office - also a time of economic pain - and as the economy recovered, so did his ratings.
With the mid-term elections less than 10 months away, Mr Obama does not have the luxury to say, as George W Bush once did: "I frankly don't give a damn about the polls."
But for now the president can console himself with an ABC News/Washington Post poll that says confidence in his leadership still greatly exceeds that in the Republicans in Congress.
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