A UN treaty banning nuclear weapons has now been ratified by 50 countries, and will come into force next January. Supporters are hailing it as a paradigm-shifting moment in the way the world sees atomic weapons. But none of the countries that have approved it, actually have a nuclear arsenal - and none of the world's acknowledged nuclear powers have signed up. All this raises doubts about how much it can achieve. Presenter: Mohammed Jamjoom Guests: Sahil Shah - European Leadership Network Beatrice Fihn - International Campaign to Abolish Nuclear Weapons Sharad Joshi - Middlebury Institute of International Studies - Subscribe to our channel: aje.io/AJSubscribe - Follow us on Twitter: twitter.com/AJEnglish - Find us on Facebook: www.facebook.com/aljazeera - Check our website: www.aljazeera.com/ #AlJazeeraEnglish #NuclearWeapons #InsideStory