Syria's war enters new year more fragmented than ever

Rebel fighters take positions inside a damaged building during clashes with forces loyal to Syria's President Bashar al-Assad who are stationed in Aleppo's historic citadel December 7, 2014. REUTERS/Abdalrhman Ismail

BEIRUT (Reuters) - Deep into its fourth year of conflict, Syria looks less and less like a state than a patchwork of warring fiefdoms, making outside powers more reluctant to intervene even as it becomes more destabilising for the region.

The United States finally entered Syria’s war this year, three years after President Barack Obama said Bashar al-Assad must leave power. But it did so only reluctantly, to staunch advances by Islamic State fighters in neighbouring Iraq, and without challenging Assad.