At a crumbling command post inside a bullet-pocked house, a militia commander was struggling to coordinate the fight against Islamic State in its Syrian capital, Raqqah.
“We entered the Old City yesterday and a group from the Free Syrian Army also came. They said they wanted to be a part of this,” Haval Bilind said Tuesday. “As you know, it’s a war, there are a lot of mortars and snipers. Now they are saying, ‘We don’t want this, we are leaving.’”
Using military radio, he tried to persuade the fighters not to withdraw. The conversation was punctuated by distant booms and the crack of nearby gunfire.
A mix of Syrian and Kurdish forces allied with the U.S.-led coalition...