WASHINGTON (NYTIMES) - The United States and Australia went to extraordinary lengths to keep Paris in the dark as they secretly negotiated a plan to build nuclear submarines, scuttling France's largest defence contract and so enraging President Emmanuel Macron that on Friday (Sept 17) he ordered the withdrawal of France's ambassadors to both nations.

Mr Macron's decision was a stunning and unexpected escalation of the breach between Washington and Paris, on a day that the two countries had planned to celebrate an alliance that goes back to the defeat of Britain in the Revolutionary War.

Yet it was driven by France's realisation that two of its closest allies have been negotiating secretly for months.

According to interviews with US and British officials, the Australians approached the new administration soon after President Joe Biden's inauguration and said they had concluded that they had to get out of a US$60 billion (S$80 billion) agreement with France to supply them with a dozen attack submarines.

The conventionally powered French subs, the Australians feared, would be obsolete by the time they were delivered.

They expressed interest in seeking a fleet of quieter nuclear-powered submarines based on American and British designs that could patrol areas of the South China Sea with less risk of detection.

But it was unclear how they would terminate the agreement with France that was already over budget and running behind schedule.

"They told us they would take care of dealing with the French," one senior US official said.

The Australians knew they had a receptive audience.

Mr Biden, who has made pushing back hard on China's territorial ambitions a central tenet of his national security policy, told aides those French-made submarines would not do. They did not have the ability to range the Pacific and show up unexpectedly off Chinese shores - adding an element of military advantage for the West.

The Australians, by all accounts, never made clear to the French that they were preparing to cancel the deal, which had taken years to negotiate.

And in meeting after meeting with their French counterparts - some including Mr Biden and Secretary of State Antony Blinken - the Americans did not give France a heads-up about their plans to step in with their own designs, the officials said, asking for anonymity to discuss sensitive diplomacy. It was a classic case of diplomatic avoidance.

Mr Biden's top aides finally discussed the issue with the French hours before it was publicly announced at the White House in a virtual meeting with Mr Biden, British Prime Minister Boris Johnson and Australian Prime Minister Scott Morrison.

The result was a blow-up that has now led to a vivid breach of trust with one of America's oldest allies.

In the end, Mr Biden's decision was the result of a brutal calculus that nations sometimes make in which one ally is determined to be more strategically vital than another - something national leaders and diplomats never like to admit to in public.

And it was a sign that as Mr Biden begins to execute what the Obama administration, 12 years ago, called the "pivot to Asia", there is the risk of stepping on political land mines as old, traditional allies in Europe feel left behind.

"As much as the pivot has been described as pivoting to Asia without pivoting away from someplace else, that is just not possible," Centre for a New American Security chief executive Richard Fontaine, who has long ties to both the Australian and American players in the deal, said last Wednesday.

"Military resources are finite. Doing more in one area means doing less in others."

It also apparently means hiding negotiations from some of your closest allies.

By the time the Biden administration began engaging Australia and Britain seriously about its emerging strategy to counter China, the three-year-old contract worth US$60 billion or more for a dozen submarines, to be constructed largely by the French, was already teetering, US officials said.

The submarines were based on a propulsion technology that was so limited in range, and so easy for the Chinese to detect, that it would be obsolete by the time the first submarines were put in the water, perhaps as long as 15 years from now.

There was an obvious alternative, the kind of nuclear-powered submarines deployed by the Americans and the British.

But US and Australian officials agreed that if the French caught wind of the fact that the plug was going to be pulled on one of the biggest defence contracts in their history, they almost certainly would try to sabotage the alternative plan, according to officials who were familiar with the discussions between Washington and Canberra.

So they decided to keep the work to a very small group of officials and made no mention of it to the French, even when Mr Biden and Mr Blinken met their French counterparts in June.

Mr Biden made no mention of the plans during a chummy chat with Mr Macron at a summit meeting in June in Cornwall, where they sat in lawn chairs by the sea and talked about the future of the Atlantic alliance. (Mr Biden, Mr Johnson and Mr Morrison met together the same day, discussed the emerging deal and, in a vague statement which seems more revealing today than it did then, referred to "deepening strategic cooperation between the three governments" to meet a changing defence environment in the Indo-Pacific.)

Three days later, Mr Morrison met separately with Mr Macron but left no impression he was rethinking the deal, the French insist.

According to French officials, Mr Blinken also stayed silent on June 25 when French counterpart Jean-Yves Le Drian welcomed him back to Paris - where Mr Blinken spent his high school years - and extolled the importance of the French submarine deal.

And as recently as Aug 30, when the French and Australian defence and foreign ministers held their annual "consultation", they issued a joint statement that said the two countries were committed to deepening cooperation in the defence industry and "underlined the importance of the Future Submarine programme".

By that time, the Australians not only knew the programme was dead; they had nearly sealed the agreement in principle with Washington and London.