Congo. One name. One mighty river. Two countries. A combined surface area greater than that of the whole of Western Europe. 250 languages. Infinite complexity. In the 2011 edition of the Human Development Index, the Republic of Congo was listed in 137th place. Its neighbour and near namesake, the Democratic Republic of Congo, was last of all: 187th, behind such bywords for chaos and conflict as Afghanistan, Syria and Yemen. What...