Nuclear weapons can fall into the wrong hands.  Even if states do not use nuclear weapons themselves, or attempt to threaten their neighbours, they can sell their technology to other, less savoury states and individuals.  This was a particular problem with Pakistan. The former head of the Pakistani nuclear program, AQ Khan, sold technology on detonation mechanisms and Uranium enrichment to North Korea and Iran. [1] Iran is also likely to be willing to pass on its own nuclear information to other states, particularly Assad’s Syria. [2]  Such weapons could also find their way into the hands of terrorists. Iran has close links to Hezbollah and Hamas which it funds substantially, and a strong desire to hurt Israel. [3] North Korea has close links to a number of nasty groups ranging from drug cartels to Islamist terrorists.  [1] Kerr, Paul K., and Nikitin, Mary Beth, ‘Pakistan’s Nuclear Weapons: Proliferation and Security Issues’, Congressional Research Service, 30 November 2011, pp.20-23,   [2] Gekbart, Jonathan, ‘The Iran-Syria Axis: A Critical Investigation’, Stanford Journal of International Relations, Vol. XII, No. 1, Fall 2010,   [3] Bruno, Greg, ‘State Sponsors: Iran’, Council on Foreign Relations, 13 October 2011,