Leading article: A chance to clear the air in Washington

Camera shots of the two leaders smiling broadly and professing great mutual admiration for one another are all but guaranteed even before David Cameron arrives in Washington tomorrow for his first bilateral talks with Barack Obama. Whether the tête-à-tête generates something more substantial than compliments concerning the health of our so-called special relationship is uncertain at this point; we must hope they do, because this is a meeting of more than symbolic importance.

Mr Cameron has business to attend to in Washington, on Europe's behalf as well as our own, and the several hours he's been allotted with the President are the best chance he is likely to have for a while to put Europe's viewpoint across. Relations between America on one side, and Britain and Europe on the other, are not exactly poor – but they could do with revitalisation.

Various issues have combined to create an air of frostiness ahead of the meeting. First, there is the row over the BP oil disaster, now morphing into a related dispute over BP's alleged role in the release of the man jailed for the Lockerbie bombing. Next come differences over Afghanistan, and over whether Western countries should spend, or cut, their way out of the economic crisis. When one factors in the presence in the White House of a man who has not concealed his intellectual and emotional distance from Europe we have the makings of a rift. That is clearly how key figures in Europe perceive matters: witness the frank complaint of the European Commission President, José Manuel Barroso, that the transatlantic relationship is "not living up to its potential".

In Washington, Mr Cameron has an opportunity, if not to iron out all these policy differences – he can hardly do that in a few hours – at least to draw some of the sting from the wounds. This is his moment to deploy his talent for bonhomie to good effect, to inject personal warmth into a relationship that is now much cooler than it ought to be.

He will have to work hard, because from the President's point of view, the visit is hardly timely. Mr Obama is deeply distracted, his presidency unpopular and his party divided and reeling from constant, increasingly vicious, Republican attacks. Still seething about the Gulf oil disaster, which has added to his political woes, his mind this week may well be on the potential disaster that could unfold in November's mid-term elections if Republicans take back both houses of Congress, a development that would turn Mr Obama into a lame duck. Faced with that prospect, only two years into his presidency, Mr Cameron could find Mr Obama nodding politely but switched off.

In Britain, some will be tempted to respond, what of it? Mockery of our insistence on the "special" quality of our ties to the US has become a national sport. Once seen as an unquestionable priority, Tony Blair's fawning attitude towards George Bush and his wrong decision to march alongside him into Iraq dealt the concept a blow in British minds from which it has never recovered. Of course, Britain's ties to America should not take the form of dog-like servility. Healthy scepticism about all our alliances is in order. At the same time, we should not underestimate the likelihood that America will remain the world's only superpower for many years, or the importance of constantly renewing our friendship with it – not least because the maintenance of our influence in the world is to a degree contingent on the state of our ties to a country much larger and more powerful than our own.

It may be true that with every passing year America becomes more orientated towards the Pacific and away from the Atlantic and Europe. Mr Obama has indeed styled himself America's first "Pacific President". All the more reason for Mr Cameron to try his hardest to keep our relationship – special or not – warm and well for as long as possible.