One evening last month, I joined a group of anti-Haftar militiamen on the outskirts of Tripoli. On the roof of a ruined villa, lanky young men scanned the front with a night vision scope. The air was heavy with the smell of sweat and rotten fruit. The LNA were three hundred metres away, on the other side of an olive grove hemmed by junipers. To our left, there were flashes of tracer-fire, the growl of heavy machine-guns and the crash of mortars. Hunkered behind a breezeblock wall, the commander on the roof was listening intently to a walkie-talkie he’d stolen from Haftar’s forces.