When it comes to national security does the need for secrecy over-ride the public's right to know? It's a hot debate in many democracies, none more so than the United States where the Obama Administration has gone after leakers and whistle-blowers with unprecedented ferocity. Stephen Sackur speaks to Thomas Drake, a former intelligence official inside America's National Security Agency. His unhappiness with things he saw led him to leak information to a reporter. He ended up prosecuted by the government he had served. Did he deserve the trouble he got?