Iran at the Table: A political solution for Syria in sight? (part 2)

For the first time since the uprising in Syria began in 2011, Tehran has been invited to talks. The US, France and Saudi Arabia had previously opposed the presence of Bashar al-Assad's main backer at diplomatic negotiations. Will this bolster Assad... or pave the way for his departure? What would be in a political deal? What stature does it give Iran? We look at how a deal over Assad would redraw the balance of power in the region.