A new joint operations room has made significant inroads into IS territory in Libya in recent weeks. The Presidency Council is making efforts to establish a new government in Tripoli, but faces both a legitimacy challenge and the continued opposition of Libyan National Army leader Khalifa Haftar.

For once in Libya, not all the news is bad. In recent weeks, Islamic State (IS) has suffered a series of reverses that have seen the area under its control significantly reduced; Tobruk’s...