A nuclear weapon in the hands of the Ayatollahs has long been a nightmare of Iran's opponents in the Middle East and beyond. So when, in 2015, the world's big powers signed a deal with Iran that prevented it from developing a nuclear bomb it was seen as a triumph for diplomacy. But the deal has always had its critics. US hawks want to scrap it or at least bring Iran back to the negotiating table. President Trump is listening, calling the deal 'an embarrassment' and 'the worst deal ever'. On Newshour Extra, Owen Bennett Jones and a panel of guests discuss the deal's faults and merits, and explore whether or not it has made the world a safer place. (Photo of an opponent of the Iran nuclear deal by Kena Betancur/AFP/Getty Images)