Leptis Magna was deserted when I last visited — no wonder. Tourists daren’t visit Libya these days and so I had the ruins to myself. I climbed the steps of the vast Roman theatre, looked out to where the Wadi Lebda meets the sea, then stopped. Men with AK-47s. My immediate fear was that they were Islamic State. Isis move closer to Leptis Magna every day and it would make sense for this most spectacular site to be next on their hit list.