It was the biggest information leak in US diplomatic history – over 250,000 US diplomatic messages or “cables” between the US State Department and US embassies all over the world – turned into a global sensation by the website WikiLeaks.

The cables dominated newspaper headlines and front pages, but what does this vast trove of documents really tell us about American diplomacy, and what impact has the leaking of the cables had?

In the first in-depth television analysis of the secret documents, Richard Bilton lifts the lid on a superpower’s secret thoughts and aspirations, plans and strategies, struggles and fears.

In this two-part series, he speaks to people at the top of the US Government about their experiences of the leaking of the cables. He finds out first-hand what the impact of the leak has been for US diplomats. And he travels to the place where the leaking of the cables helped fuel revolution.

He unpicks what the cables really tell us about the world’s greatest superpower, the stories America did not want you to hear – the difference between what the US says in public and what it says in private.