The latest addition to my website is John Lanchester‘s The Wall. This is a post-apocalyptic novel about a country which has a wall entirely round its coastline (some 10,000 km) to keep out refugees. The country is presumably based on Britain. There has been an event called The Change, which has involved major flooding all over the world due to rising sea levels, presumably because of the melting of the polar ice caps. In the first part of the book, we follow a man called Kavanagh. The country requires everyone – men and women – to serve for two years as Defenders, keeping out any refugees trying to breach the wall. If any refugees do get through, the Defenders on that part of the wall are put into a boat, towed out to sea and abandoned to their fate. We follow the adventures of Kavanagh and his fellow Defenders, before turning to the story of some refugees in the second part of the book. This book was presumably written in the light of the proposed Trump wall and the refugee crisis in Europe and elsewhere and tells an effective story, but how much would a 10,000 km wall cost?