Sometimes lowering the volume is as arresting as turning it up. Tact can be as expressive as bombast. That is true of the coalition government's diplomacy. It has been eloquently muted, with both old problems and the oozing challenge in the Gulf of Mexico: a British administration that some expected to be spikily assertive seems determined to get along with everyone.

Right-wing British newspapers are often every bit as shrill as the American media. Leaping on the chance to display some easy, knee-jerk patriotism, several urged British PM David Cameron to stand up for "British Petroleum" and rebuke US President Barack Obama for demonising the company. Instead, the line has been that the government neither owns nor will disown BP and quietly to point out that the firm has lots of American shareholders and employees too. Ministers saw Obama's rhetoric for what it was: the flailing of a politician in a desperate fix. By saying very little in public, they defused what threatened to become a juvenile spat.

It would have been foolish to do otherwise. More striking has been the emollient attitude to Britain's friends in Europe. Cameron's debut reception is likely to be warmer than once seemed plausible at the European Council in Brussels. The impressively polyglot deputy prime minister, Nick Clegg, has helped to soften up continental leaders who were troubled by the idea of a Conservative-led government. In David Lidington, Cameron appointed a Europe minister who is much more palatable to the neighbours than Mark Francois, the Tory who held the brief in opposition. Even William Hagueunusually, in recent times, a foreign secretary who is both a big-hitter and an eager holder of that office is sounding relatively Euro-friendly. It helps that, as part of their deal with the Liberal Democrats, the Tories ditched their quixotic bid to repatriate powers from the EU.

The prime minister has already visited Afghanistan, where he embraced Britain's fighting men more convincingly than his predecessor, Gordon Brown, ever managed to. He calls their fight a ‘war', rather than the pussyfooting ‘conflict'. Yet for all Cameron's vows to stay the course, his underlying message was humble. The definition of victory in Helmand has been revised downward (a process that began under Brown); simultaneously, the official view of how close British forces are to achieving their diminished goals is being revised upwards. The length and scale of the deployment still largely depend on decisions made in Washington. But Cameron's government seems increasingly keen to pull back as soon as it possibly can.

What explains this modest and conciliatory mood the urge to ingratiate rather than swagger? The nature of the coalition is part of it. Foreign affairs were widely billed as a potential source of fractures in the Lib-Con double act. So far, they haven't been. The mixed Foreign Office ministerial team, and the cabinet's European-affairs committee, are said to be dreams of harmony.

Cautious mentality

The less proactive foreign policy is, of course, the longer that unity can be made to last: it is generally easier to agree on not doing things than on doing them. More than that, though, the two parties' world views may prove more reconcilable than they once seemed. The Tories harbour a neocon tendency; the Lib Dems have a pacifist wing. But there is also a realist strand in Tory thinking and a sane but quietist strain among Lib Dems. A cautious, status-quo mentality is where they overlap.

Another part of the story is money, or rather the lack of it. It doesn't take the strategic-defence review, to be completed this autumn, to understand that very soon Britain will have less to spend on military kit and adventures, perhaps a lot less. And the impact of the country's fiscal plight on its ability and inclination to project power is much wider than that. Even more than is the case already, political energy and capital will soon be overwhelmingly consumed by domestic woes. Moreover, Britain's standing and esteem abroad have been punctured by the crashing end of its economic boom.

In these political and economic circumstances, modesty and niceness are a sensible strategy. The understated tone suggests a government suitably aware of its limitations. How nice the world will be in return, however, is doubtful.

Even before the oil spill, some Britons worried that Obama was predisposed by his Kenyan ancestry to dislike them. But he is most usefully thought of, not as a post-colonial president, but as a post-war one the wars being the Second World War and the cold war. Obama is probably too rational to bear the grudge against Britain that some detect in his railing against BP but also too rational to be sentimental about the place.

Meanwhile, enchanted as the Europeans may be by the British new boys, and however mature Cameron plans to be in his EU dealings, there will, in the end, be rows: over financial-services regulation, oversight of national budgets, the British rebate, reform of the common agricultural policy… There always are.

As before, Europe is an opportunity but also an irritant; Britain is still locked into a gradual, half-willing decline, destined to be less loved by its closest ally than it would like. Those are the facts. No amount of ingratiation can change them.