The threat of a nuclear-armed Iran is "real" for the United States but Al-Qaeda poses an even greater danger, US Secretary of State Hillary Clinton said Sunday. "In terms of a country, obviously a nuclear-armed country like North Korea or Iran pose both a real or a potential threat," Clinton told CNN's "State of the Union", making it clear the Iranians don't yet possess an atomic weapon. "But I think that most of us believe the greater threats are the trans-national non-state networks," she said, referring to Al-Qaeda and its affiliates in Afghanistan, North Africa, Pakistan, Saudi Arabia and Yemen. Clinton voiced concerns about Al-Qaeda's level of "connectivity" and said Osama bin Laden's terror networks were continuing to "increase the sophistication of their capacity" and the kind of attacks they were planning. The US city of Detroit had a narrow escape on Christmas Day when a young Nigerian claiming allegiance to Al-Qaeda, Umar Farouk Abdulmutallab, botched an attempt to bring down a packed transatlantic airliner as it began its descent.