by Paul Reynolds
BBC News Online world affairs correspondent
The British government was furious that it had not been consulted or properly informed about a worldwide nuclear alert called by the United States during the Yom Kippur war in October 1973.
PM Edward Heath expressed his fury in a memo
In a stinging memorandum, just made public under the 30 year rule, the British Prime Minister Edward Heath virtually accused President Nixon of diverting attention from the Watergate scandal.
"We have to face the fact that the American action has done immense harm, I believe, both in this country and worldwide," he wrote.
"We must not underestimate the impact on the rest of the world.
"An American President in the Watergate position apparently prepared to go to such lengths at a moment's notice without consultation with his allies.....without any justification in the military situation at the time."
The episode is an example of how quickly a divide can open up between the United States and its allies.
Nuclear alert: Forces ready to act
Mr Heath remarked that he had heard of the alert from a news agency wire. He wrote: "When I asked the Foreign Secretary [Sir Alec Douglas-Home] about this, sitting next to him on the bench as he was about to make a statement, he was in the same position."
The problem was compounded by an apparent attempt by the US Secretary of State Henry Kissinger to downplay the alert and by a failure within the British Government to pass on information.
The alert raised US military readiness to Defcon 3 - "defence condition" three.
There are five such stages and condition three means that all forces, including nuclear forces, go on a high state of readiness.
It was called after a message to President Nixon from the Soviet leader Leonid Brezhnev.
Brezhnev gave a warning that the Russians might intervene in the fighting between Israel and Egypt, the Israelis by that stage having gained the upper hand after General Ariel Sharon (now Israeli prime minister) had crossed the Suez Canal.
Role of Dr Kissinger
According to an assessment of the alert by the Joint Intelligence Committee, Dr Kissinger did tell the British ambassador in Washington Lord Cromer about the alert but mentioned it in a "puzzling" way.
He told Lord Cromer about "a low level of military alert with cancellation of leave to affected naval and military in the neighbourhood of hostilities."
"It is difficult to reconcile this statement," the JIC noted, "with the imposition of Alert Stage 3 which involved American forces, including their strategic forces, throughout the world."
Slow response in London
Lord Cromer was informed by Dr Kissinger at 0515 London time
The alert went into effect at about 0600. Cromer called London at 0620 but nobody seemed to take the alert very seriously.
Nobody told the Prime Minister or the Foreign Secretary.
At 0730, the duty intelligence officer at the Cabinet office learned of the alert from GCHQ (the government's electronic monitoring centre). GCHQ had been told by the Americans on the intelligence network.
It wasn't until 0800 that the US Navy formally signalled the Nato countries.
Allied anger at the subsequent Nato meeting was directed at the then ambassador Donald Rumsfeld, now secretary of defence, and American documents show that he was quite sympathetic to their complaints.
There was one further detail, which illustrates the lack of communications.
The Nato meeting, at which the alert was explained, started at 1145 and ended at 1330.
Yet the British ambassador did not send a message to London until 1425. Edward Heath asked why.
The ambassador's excuse was that he had been in the meeting on his own and "had no one to whom he could pass his notes for earlier transmission."
The JIC concluded that the alert was not necessary in military terms: "We are inclined to see the US response as higher than necessary to achieve the desired effect," it said.
Dr Kissinger has always said that it was justified as it ensured that the Soviets would not act. Recent interviews with Soviet officials indicate that it was a bluff by Brezhnev in the hope that the United States would force the Israelis to stop.