Torture and CIA "ghost" prisons will be no more. Guantanamo Bay will be closed. Lo and behold, the leader of communist Cuba has called the 44th President of the United States "an honest man". The latter will, after all, have a BlackBerry, while the White House boasts a slick new website where news releases are repackaged as the Blog. Truly, in the first 100 hours of Barack Obama, change has come to America.

In fact, change arrived in his first 100 minutes – before even the olive-green presidential helicopter carrying George W Bush into retirement had lifted off from the east plaza of the US Capitol, to the relief and joy of the two-thirds of Americans long sick of the sight of him. In these first four days in office Obama has made many decisions, some symbolic, some of substance. But nothing signalled a new era more powerfully than the inaugural address itself, his first official act after taking (incorrectly, as it transpired) the Oath of Office.

More explicitly than almost any inaugural in history, the 21-minute speech repudiated the attitudes and policies of a departing president. The Bush administration's scorn for internationally stipulated rights of prisoners, its disregard for science, its high-handed foreign policy, and its blind veneration of the market – Obama disowned them all. So much so, indeed, that some Bush staffers went public with their fury when they learnt of the speech's contents. And though much, much more will be done in the weeks and months to come, Obama has made a real start in turning words into deeds.

Download the new Independent Premium app Sharing the full story, not just the headlines

On foreign policy, Guantanamo Bay is only a part of it. Quickly focusing on the Middle East, where every gesture of a US president is minutely parsed, Obama chose to make his first foreign call to Mahmoud Abbas, the Palestinian President. Only then did he speak to the leaders of Israel, Egypt, and Jordan. Obama, as he must, says America's support for Israel is unswerving. But few other presidents have spoken as forthrightly as he did at the State Department last week about the human suffering of the Palestinians in Gaza, or insisted as strongly that the border must be opened.

The choice of George Mitchell, the skilled Lebanese-American negotiator and former Senate majority leader, as special envoy to the Middle East at last brings a genuinely honest US broker to bear on the crisis, as the parties to Northern Ireland's peace accords can testify. Much the same goes for the hard-driving Richard Holbrooke, architect of the 1995 Bosnian accords, who will play an equivalent role in Afghanistan and Pakistan.

On the home front, there have been comparable symbolic decisions in these first 100 hours. Obama has moved to clamp down on lobbying excesses. He has issued executive orders to make government more transparent. To show he realises the misery faced by millions of ordinary Americans, he has ordered senior staffers to accept a pay freeze that for some amounts to a pay cut. As well as his traditional intelligence briefing, the new President will now receive a similar daily economic briefing from his top White House economic adviser, Larry Summers.

Naturally, there are ample grounds for scepticism. Every incoming president vows war on lobbyists, that peculiarly Washington species which greases the financial wheels of political campaigns and which – especially when Republicans were in control – sometimes virtually wrote congressional legislation. On paper, the restrictions Obama announced on Wednesday are severe.

No one who has lobbied the government within the past two years will be able to serve in the new administration, and once they leave it, they will be barred from lobbying – not for a single year, as was the case under Bush, but for as long as Obama remains in the White House. Alas, the 44th President has already broken his own rule by naming as Deputy Defence Secretary (the hugely important job held by Paul Wolfowitz in the run-up to the Iraq War) a former defence industry lobbyist named William Lynn.

Ditto the Obama campaign promise to reduce partisanship in Washington. The inaugural address showed his willingness to listen to different points of view: "The question is not whether government is too big or too small," he declared, "but whether it works." On Friday he summoned both Republican and Democratic leaders to the White House to press the $825bn economic stimulus package now wending its way through Congress.

So far, so good. But every president takes office promising greater political civility. After all George W Bush, one of the most polarising presidents ever, was pledging back in January 2001 to be "a uniter, not a divider". And for all the professions of sweetness and light on Capitol Hill, some Republicans are digging in against the economic measure, accusing the Democratic majority once again of ignoring them. Plus ça change.

Daily coronavirus briefing No hype, just the advice and analysis you need Enter your email address Continue Continue Please enter an email address Email address is invalid Fill out this field Email address is invalid Email already exists. Log in to update your newsletter preferences Register with your social account or click here to log in I would like to receive morning headlines Monday - Friday plus breaking news alerts by email Update newsletter preferences

Many presidents also take office promising greater openness. On this score, too, Obama last week delivered handsomely, by lifting restrictions on the Freedom of Information Act, and reversing a Bush-era order that allowed presidents and their heirs to refuse to release records on the grounds of executive privilege. Both moves delighted historians – and they may soon be embarrassing the super-secretive previous administration.

But do not get carried away. Obama is no great lover of the press. His campaign's strategy of keeping the press at arm's length worked so well that it irked many journalists. The approach may well be continued, breeding similar resentment. The affable Robert Gibbs, the new presidential spokesman, was given a gentle ride at a packed first briefing on Thursday. Hours later, however, the man they call "no-drama Obama" sounded distinctly testy when he visited the cramped press working quarters by the briefing room, only for reporters to pepper him with questions about Lynn.

Even Hillary Clinton's ecstatic reception at the State Department last week raised some disconcerting memories. Eight years ago the no less charismatic Colin Powell arrived in the building, promising a new dawn for US diplomacy – only to lose out to Donald Rumsfeld's Pentagon across the board. No one is saying the same will happen now. It is merely a reminder that the heady talk of the first 100 hours can be just that: talk.

Already, though, Obama has served notice he will be a pragmatist: "I'll listen to any good idea, wherever it comes from," he is fond of saying. More important, unlike his predecessors Bill Clinton and George W Bush, he bears no scars from the fractious and divisive 1960s. A Democrat he may be, but he is not a knee-jerk liberal. Once his nomination was secure last summer, for instance, Obama watered down his earlier opposition to Bush's use of warrantless domestic wiretapping as part of the "war on terror", a programme that was anathema to the left.

Pragmatism also means accepting the facts. In that inaugural address, no slap to his predecessor was more stinging than his vow to "restore science to its rightful place". The news delighted not just the academic community, which watched, frustrated and helpless, as the Bush administration doctored expert reports and shaped policy on global warming, stem-cell research and the like, to suit its ideology – even its theology. The halt on federal aid for stem-cell research announced in 2001 could be reversed soon, while a ban on government funding for groups that offer abortion counselling abroad has already been lifted.

In fact, the crucial early decisions of the Obama administration, including ones on another bank bailout and the fate of the US car companies, are yet to come. In that sense, last week was merely the beginning of the beginning; even the burning matter of the family dog (labradoodle or Portuguese water dog?) is unresolved. Already, however, the style has changed utterly. Pragmatism is replacing ideology, talking past people is out, talking to people is in. No shock in these last few days has been greater than a president who speaks in grammatical sentences, who pauses an instant to ponder a question before answering it. Obama's calm and preparedness are remarkable. It's almost as if he had been anticipating this moment for years.

Bush's great hero was Winston Churchill. But if any recent US president at this stage in proceedings reminds one of Churchill – and his words about May 1940 that "I felt as if I were walking with destiny, and that all my past life had been but a preparation for this hour" – it is somehow Obama. "He looks very comfortable in his surroundings," Robert Gibbs said of his boss, and this time a spokesman's words didn't just sound like spin.

Inauguration day: How the supporting cast fared

Winners

Dick Cheney, in a wheelchair, passed audition for 'Dr Strangelove' remake.

Aretha's hat, which stole the show, was her own design.

Labradoodles. Barack will have to fulfil his pledge of a new White House puppy.

The first granny, Marian Robinson, 71, has been persuaded to move into the White House to help ground the Obama girls.

Robert Gates, Defence Secretary, who stayed in a warm "secret location" in case of an al-Qa'ida attack.

Losers

The BBC's Huw Edwards, who persistently talked over momentous events.

Malia and Sasha Obama, who will still get only $1 a week pocket money and will have to scoop the new puppy's poop from the White House lawn.

Jill Biden, whose red coat made it look as if she'd forgotten her skirt.

Laura Bush, who now faces the prospect of a retired George W under her feet.

The Guardian's US experts, usurped by editor Alan Rusbridger, who decided he could do the front-page story better than them all.

The first 100 hours

Day 1: Tuesday 20 January

12.05pm (Washington time) Barack Hussein Obama is sworn in by Chief Justice John Roberts. Both stumble over the words.

12.09pm President Obama gives his inaugural address.

1pm Signs his first official documents and moves to a private lunch with congressional leaders.

3.20pm Parade begins and the Obamas take their place in their state-of-the-art limousine.

6.45pm Instructs government agencies to suspend military tribunals in Guantanamo Bay for 120 days.

8.37pm Ball no 1: the Neighborhood Ball, where he has his first dance.

9.55pm Ball no 3: The Commander-in-Chief Ball.

10.35pm Ball no 4: the Youth Ball.

12.45pm Ball No 10: Eastern States Ball. Reminds supporters that "This is not the end, this is the beginning."

Day 2: Wednesday 21 January

8.35am Obama enters the Oval Office. Reads the letter addressed to President no 44 from no 43. Consults chief of staff, Rahm Emanuel.

9.30am Attends prayer service at National Cathedral.

12.30pm First calls to foreign leaders are to Palestinian Authority President Abbas, Israeli Prime Minister Olmert, Jordan's King Abdullah, and Egypt's President Mubarak.

2pm Obama's first executive orders prevent former lobbyists from working for agencies they had lobbied, freeze salaries of staff earning over $100,000, order agencies to co-operate with Freedom of Information Act and limit powers of former presidents to block the release of sensitive records. Holds meetings with Iraq military commanders and economic advisers.

7.35pm Justice Roberts administers the Oath of Office to Obama for the second time in the White House.

Evening Attends the Thank You Ball for campaign workers.

Day 3: Thursday 22 January

12 noon Obama signs orders closing the detention camp at Guantanamo Bay within a year; ending the CIA's network of secret prisons; and requiring all interrogations to employ non-coercive methods.

Afternoon Appoints former senator George Mitchell, who negotiated the Belfast Good Friday agreement, as special envoy to the Middle East. Also appoints Richard Holbrooke, former UN ambassador, as special envoy to Pakistan and Afghanistan.

Evening Gets confirmation that he can keep his BlackBerry.

Day 4: Friday 23 January

2.45pm Meets Democrat and Republican Congressional leaders to encourage them to pass the $825bn (£607bn) stimulus package.

Afternoon Telephones Prime Minister Gordon Brown.

7pm Issues orders repealing rules that restricted federal money for international organisations promoting abortions overseas.

Sarah Hiddleston

Obama by numbers

40,000 security personnel on duty or on stand-by in Washington DC during Obama's inauguration last Tuesday.

5,000 portable toilets set up for a public turnout that topped two million.

67 per cent approval rating for Obama in poll on the day he took office.

4 Middle East leaders were called by President Obama last Wednesday.