Leading article: One year on, Barack Obama has made a promising start

When Barack Obama was inaugurated one year ago today, the excitement and anticipation were exceptional even for a land renowned for celebrating new starts. A youthful 47 and only a first-term Senator, the first non-white US President was a one-man smasher of moulds and glass ceilings whose election victory had inspired euphoria in the United States and hope around the world.

Life can play cruel tricks. The new President took office with an approval rating of more than 80 per cent. One year on, his popularity hovers around the 50 per cent mark. Yet the balance in no way justifies such a decline. Even at this early stage, the disappointments are far outweighed by the hopes that have been kept alive.

In part, the discrepancy is to be explained by the stratospheric expectations Mr Obama raised, not only by his election but by the uplifting campaign he fought, a campaign given wings by his enthusiasm and his oratory, which brought millions of Americans into politics for the first time.

Such high expectations were never going to be met. But it is far too soon to forecast that the chorus of "Yes we can" will decay into a sullen "No we can't". A positive sign is the upturn in his ratings following Washington's can-do response to the Haiti earthquake. For all the criticism, the US has mounted a vast operation at great speed, with the versatility required in extreme circumstances. This is an exemplary use of US might; it is cheering that Americans recognise it as such.

Operations in Haiti, though, are just a tiny part of the grand transformation Mr Obama has wrought in the way the world now sees his country. The image of the unilateralist bully was supplanted almost overnight by a new, more generous, more collaborative, more culturally sensitive America in the best tradition of liberal internationalism. If in his first year, Barack Obama had achieved only this – the global rehabilitation of his country – it would have been no mean feat. But he did not.

At home, he has steered the US through its worst financial crisis since the Depression. He has shown competence, singleness of purpose and a keen awareness that ordinary tax-payers will bear the brunt of the liabilities. If this sense of common cause is expressed more in words than deeds, that does not necessarily make it ineffective. A President's job is also to set a tone.

Mr Obama has also come closer than any other president to tackling the disgrace of a healthcare system that fails to cater to 20 per cent of the population. Given the alliance of vested financial and political interests ranged against him and the fear of many Americans that any change will mean worse, this is a formidable achievement. Final success hangs in part on the Senate race in Massachusetts – whose closeness says much about the gap between US expectations and experience of Barack Obama's presidency – but the battle is not yet lost.

The nature and ferocity of opposition to his healthcare legislation offers another clue to his ratings. On one side are the Republicans, raring to tap grassroots' suspicions of liberals in this year's mid-term elections. On the other are Democrats unhappy with the compromises he has had to make to secure any reform at all. He is caught in this pincer.

And there are disappointments elsewhere. He has missed his own deadline for closing Guantanamo, despite the bold – and laudable – decision to try some detainees in US courts. The timetable for withdrawal from Iraq is longer than many hoped. Despite his great efforts to clarify the mission, Afghanistan remains a costly and ill-defined enterprise. At times, his decisions have seemed hesitant. He could also have wished for more willing partners among those Muslim leaders to whom he extended his hand in return for their unclenched fist.

Yet the world of Mr Obama's first year is a generally more amenable place than it was. To count on an advance in a Middle East peace process that has already taken decades was unrealistic. Expectations of Iran must remain suspended so long as the state is in disarray. Patience is a virtue in a statesman, and a quality this President has not had to learn.

What his first year has exposed, less than any personal limitations, are the constraints on the power of all US presidents. The supposedly most powerful individual in the world can do no more than he can square with Congress. Abroad, he is additionally restricted by sensitivities and events beyond his control. These are early days and this has been an eventful 12 months. Whether it was a promising beginning to a great presidency, or – more sombrely – as good as it gets, is a question that will be answered in the next three years.