In an article, published in the Economic Journal in 2014, "The Need for Enemies", the authors argue via a model, which they test, with data from Columbia's antiterrorist programmes, that where some politicians have an edge in undertaking a task and this gives them electoral advantage, there is an incentive to underperform in the task. From the abstract, they say, "Politicians need to keep enemies alive in order to maintain their political advantage". There are plenty of examples in British Politics where this seems true. ...