FOR the third time in a week, Barack Obama has found himself trying to placate the leaders of closely allied nations who have discovered the extent of NSA surveillance in their countries. As the flood of spying scandals threatens to engulf the White House, it has raised the question over whether the negotiating edge such secret eavesdropping provides is worth the reputational damage to Washington once it is secret no more, mostly as a result of the revelations of former NSA contractor Edward Snowden.

With each leak, American soft power haemorrhages, and hard power threatens to seep away with it.At the summit level, deal-making is personal. Now that the US under Obama has acknowledged it cannot act alone on the world stage, relationships between leaders can make the difference between success and failure. The recent wrangling over Syria in the UN security council is a recent and vivid illustration.

Yet nothing could be more personal for a foreign leader than to find their own mobile phones tapped by a nation they considered an essential friend and ally. That appears to be the case for Angela Merkel, as it has been for Mexico's Enrique Pena Nieto. The other humiliating phone call of the week was on Monday with Francois Hollande, whose phone was not bugged as far as he knew, but who demanded an explanation for the revelation — once more from the Snowden files — that the NSA had been recording tens of millions of French phone calls a month. The White House was forced to admit that the evidence raised “legitimate questions for our friends and allies”.

Top of that list of questions is what exactly does it mean to be an American ally in the 21st century. Germany and France are Nato partners. Their soldiers have fought and died alongside American troops in Afghanistan. Mexico is fighting a bloody battle with drug cartels with America and on its behalf.

The Brazilian president, Dilma Rousseff, whose phone was also monitored by the NSA, was an American critic but by no means an adversary.

The same sort of questions are being asked of Britain, after the Guardian revealed that GCHQ spied on the delegations the UK had invited to the G20 summit in London. It turned out that the internet cafe laid on for foreign diplomats had been rigged specifically so that GCHQ could read outgoing emails. Among the targets were the finance minister and other officials from Turkey, another Nato ally that considered Britain to be its closest friend in Europe, and a close partner over Syria.

Belgium, another old ally, found evidence its main telecoms provider, Belgacom, had undergone a powerful cyber attack apparently from GCHQ, in a scheme codenamed Operation Socialist aimed at “better exploitation” of Belgian communications.

It is clear from the trove of documents leaked by Snowden that the only protection against NSA or GCHQ intrusion is membership of Five Eyes: the US, UK, Canada, Australia and New Zealand.

New members do not seem to be welcome, and the lesson is that outside that tight circle, it does not matter how senior you are, and how close a friend you think you are to Washington or London, your communications could easily be being shared among the handful of white, English-speaking nations with membership privileges.

By arrangement with the Guardian