By Jonathan Beale
BBC News, Washington
Could the case of Binyam Mohamed end the the special relationship?
A lot of nonsense is written about the so-called "special relationship" based on the assumption that it entirely depends on the chemistry - or lack of - between a British prime minister and a US president.
The reality is that the roots go far deeper.
Intelligence-sharing is one of the main reasons why the relationship between America and Britain remains "special".
A former senior US official told me it was in fact the "backbone" of the relationship.
The CIA and Britain's intelligence services - MI6 and MI5 - cooperate closely, more than any other country.
The common language helps. But it is more than that.
Degree of trust
There is a degree of trust - and that counts in a world based on espionage and suspicion.
Remember President Bush used British intelligence - without the caveats - to help make his case for war with Iraq.
The two nations' intelligence agencies are now co-operating closely on Iran and Pakistan.
MI6 officers are regular visitors to the CIA's headquarters in Langley, Virginia, and CIA officers are no strangers to 85 Vauxhall Cross.
That is why the British government is just as vociferous as the Obama and Bush administration in opposing the publication of any US intelligence on Binyam Mohamed.
If released it would cause harm. But an end to the "special relationship"?
Perhaps not. Remember Kim Philby and the Cambridge spy ring uncovered at the height of the cold war?
Britain and America's relationship has survived much worse.