Image caption David Cameron said he would work to redefine the "special relationship" during a visit to the US in July

The leaked diplomatic cables from the US embassy in London show the reality of the American relationship with Britain.

It is entirely based on what the US national interest is. That, of course, is natural. Diplomats are sent abroad to act for their own country not anyone else's.

It is notable there is no sentiment in the cables. There is hard-headed assessment.

Therefore, in a report for the new Obama administration, the embassy's deputy chief of mission Richard LeBaron urges a particular tactic for the new team - reassure the British about the strength of their relationship with the US.

"It is not in US interests to have the UK public concluding the relationship is weakening, on either side.

"The UK's commitment of resources - financial, military, diplomatic - in support of US global priorities remains unparalleled; a UK public confident that the US government values those contributions and our relationship matters to US national security. This is a theme Embassy London stresses privately and publicly," he says.

In fact Mr LeBaron's theme is that all is well underneath, despite what he clearly feels is an obsessive British preoccupation with the "special relationship".

The British, for example, were "overreading" the signs of a change under President Obama, like the return to the British embassy in Washington of a Churchill bust on loan to George W Bush.

"Although this period of excessive UK speculation about the relationship is more paranoid than usual, we agree with a senior MP who told us that ultimately 'the people who really matter in all this, those who do the serious business, know that where it matters - over defense, security issues, intelligence-sharing - the relationship is deep, ongoing and abiding'," he says.

The senior MP turns out to be Labour MP John Spellar, then a government whip.

Tensions

Mr Spellar incidentally predicts a falling off in approval for the new president.

He is quoted as saying: "At the moment, there's unrealistic euphoria towards the new president... MPs are forgetting that, ultimately, presidents have to behave in a certain way. Some of us are destined to be disappointed by him, policy-wise."

However, another MP, Brooks Newmark, who studied at Harvard, warns of tensions.

"Brooks Newmark, a Tory MP who follows defense issues, [said] he fears an erosion in UK public support for continued engagement in Afghanistan because of the 'criticism of our troops from US military commanders and others in Washington,' which Newmark believes will also drive a wedge between the administration and Downing Street."

Image caption William Hague reportedly described top Tories as "staunch Atlanticists"

This criticism of UK forces has been highlighted in the Wikileaks revelations, with Secretary of State Hilary Clinton having to weigh in to reassure the British, very much in line with the policy the London embassy recommended.

The cables also confirm some very pro-American attitudes by the then soon-to-be Conservative defence and foreign secretaries, Liam Fox and William Hague.

Mr Hague in particular is interesting in that he is not reported as telling Mr LeBaron in private what he later said in office about not being "slavish" towards the United States.

In his report, Mr LeBaron quotes Mr Hague as saying that he and other Conservatives were "children of Thatcher", though he accepts they "sit at the top of the pyramid of the general public and it is unclear whether the British people will maintain the network of ties to America that has sustained the special relationship."

One interesting aside mentioned by Ambassador Susman in his report of the meeting with Liam Fox is that he quoted Dr Fox as saying that the international negotiations with Iran would "fail".

There was however no follow-up as to the implications of that.

The overall impression given by these telegrams is that Britain is regarded as a useful asset for the United States and that it must not be allowed to think otherwise.

But the underlying message of all this is that the relationship is defined in this way and if, or probably more likely when, the day arrives when the Brits cannot or will not offer so much, they will find that the relationship they still regard as "special" will be very much more ordinary.

paul.reynolds-INTERNET@bbc.co.uk