Larry Sabato: His fate will be shaped by events beyond his control

As we look back on a tumultuous first year for President Barack Obama, three questions matter. What have we learnt about him? What has he learnt about his job? And how much does the first year foretell about his presidency?

In many ways, Obama in office has acted much as advertised on the campaign trail. He is methodical, cerebral, professorial, and unusually focused. "No Drama Obama", as he is called, isn't given to angry outbursts, emotionalism of any kind, or snap decisions. Many people prefer this kind of governing style, though it limits his effectiveness at times of national anguish and prevents him from employing populist tactics that could aid him politically.

Obama trusts and follows his instincts, even when he pays a political price. He took months to formulate a clear approach on Afghanistan, and the more criticism he received for the length of his policy review, the more determined he seemed to dot every i and cross every t before announcing his plans.

The Afghanistan decision-making also showed us something else. Despite his image as a political liberal, Obama is usually cautious to a fault, splitting the difference whenever necessary.

He is no revolutionary, as the disappointed left wing of the Democratic party has now discovered. From Guantanamo to healthcare, the President has compromised, whether his party base is happy or not.

Like every new president, Obama has been forced to accept the unpleasant realities of the Oval Office. His soaring campaign rhetoric suggested easy solutions to intractable problems. The first 12 months have shown him just how unyielding those problems are.

An economy the size of the United States's does not respond quickly – even to a massive $800bn stimulus bill. The unemployment rate, a lagging indicator, has climbed rather than fallen on Obama's watch.

The candidate of "hope" and "change", had expected his gestures of friendship to tame hostile world leaders. Instead, he could not even secure the Olympics for his home city of Chicago. A Nobel Peace Prize brought him more ridicule than praise.

At home Obama believed he could initiate a new era of bipartisanship. In fact, with his own popularity dwindling from an approval rating in the 70s last January to the 40s today, he has further polarised the American electorate. The President has been tagged a big spender, taxer, and debt accumulator – a damaging image that is likely to stick with him and his party for some time to come. Republicans are in the ascendancy again, and they are likely to do well in the November midterms.

The recent, nearly successful, airliner bombing attempt jarred Obama. He had hoped to focus more on domestic policy, but on Christmas Day he was reminded that terrorists never take a holiday.

A year is a short time, but it is a quarter of a presidential term. Year one is usually the most productive period and Obama has had a remarkable advantage, with Democrats controlling Congress by a huge margin – a 40-seat majority in the House of Representatives and a filibuster-proof 60 seats in the Senate. So controversial have many of Obama's bills been, he has needed every vote available .

Yesterday's contest for Ted Kennedy's old seat has demonstrated how much opposition exists to Obama's programmes even in a liberal state like Massachusetts, which he carried with 62 per cent of the vote. Skittish Democrats, facing a difficult election, will now be far less willing to cast tough votes for Obama. Even if he serves two full terms, Obama is unlikely ever again to have anything approaching the current Democratic numbers in the legislative branch. With less congressional and voter backing, Obama is facing a far more difficult phase of his presidency.

Historically, presidents are rarely made or broken by their first year, and in that sense it is not a good barometer of how they will fare for re-election. Jimmy Carter and George Bush Sr had splendid first years and enjoyed high popularity then lost in landslides after a single term. By contrast, two-term presidents Ronald Reagan and Bill Clinton had troubled first years and didn't hit their stride until much later.

Like his predecessors, Obama's future depends less on what we have seen so far and more on the circumstances of history awaiting him. The shape of the economy and the vagaries of terrorism will shape his fate. Only now is this young, vigorous President realising how little he controls either one. His second year will continue the education, and one suspects it will take place as much in the school of hard knocks as in the comfortable confines of the White House.

The writer is the author of The Year of Obama and director of the University of Virginia Centre for Politics