![An anti-Brexit demonstration at Houses of Parliament on October 10, 2018](https://s.wsj.net/public/resources/images/FN-AE920_FN_BRE_M_20181016123913.jpg)
The United Kingdom’s “Remainers,” who still hope to reverse Britain’s decision to leave the European Union, have placarded British cities with a simple question: “Brexit – Is It Worth It?” Well, is it?
The answer given by economics is clear: certainly not. In terms of the costs and benefits of leaving, the result of the 2016 Brexit referendum was plainly irrational.