As the devastating war in Syria entered its fifth year Sunday, the US said it would have to negotiate with Syrian President Bashar al-Assad as it aims to "reignite" new peace talks. More than 215,000 people have been killed and half of the country's population displaced, prompting human rights groups to accuse the international community of "failing Syria." Amid the dragging stalemate on the ground, the country has been carved up between government forces, jihadist groups, Kurdish fighters and the remaining **n-jihadist rebels. Diplomacy remains stalled, with two rounds of peace talks achieving ** progress and even a proposal for a local ceasefire in the second city Aleppo fizzling out. After years of insisting Assad's days were numbered, US Secretary of State John Kerry conceded Washington would have to negotiate with the iron-fisted leader to end the war.