Washington: The release of a quarter of a million US diplomatic cables leaked by Chelsea Manning, the US army whistleblower whose 35-year sentence was commuted by President Obama on Tuesday, had a powerful impact on the practice of diplomacy around the world.

From November 2010 on, the knowledge that their classified reports might ultimately go viral online made US diplomats think twice about what they wrote back to Washington and made their foreign contacts think twice about what they told the diplomats.

The cables may even have played a part in sparking the Arab Spring revolt. The colourful accounts of the opulent lifestyles of the family of Tunisian president Zine Al Abidine Bin Ali, circulated on Twitter and Facebook, acted as an accelerant to the rage of the country’s disaffected youth.

In one of the more colourful cables of the cache, the US ambassador to Tunisia, Robert Godec, described a 2009 dinner with Bin Ali’s daughter and her husband, a wealthy businessman, Mohammad Sakher Al Materi, who owned a pet tiger, fed on a constant supply of chickens, which reminded Godec of Uday Hussain’s lion in Baghdad.

“After dinner, [Al Materi] served ice cream and frozen yoghurt he brought in by plane from Saint Tropez, along with blueberries and raspberries and fresh fruit and chocolate cake,” the cable reported.

The report spread instantly and far around a country where it was estimated that 2 million out of 10 million people were Facebook users. It is impossible to say whether it had been read by Mohammad Bu Azizi, the fruit seller who set himself on fire a few days after the Godec cable was published in protest at harassment by the municipal authorities, but it had certainly been seen by a large number of protesters who came out on the streets in response to his suicide.

The leaks also revealed that US diplomats had been ordered to take part in an intelligence-collection operation at the United Nations targeted at the secretary general, Ban Ki-moon, and the permanent Security Council representatives from China, Russia, France and the UK.