The release of FBI agent Peter Strzok’s text messages has touched off a partisan debate in Washington over whether his anti-Trump and pro-Hillary Clinton comments undermine his work on the Clinton email as well as the Russia investigation being conducted by Special Counsel Robert Mueller. Republicans argue that Strzok’s texts, which he exchanged last year with Lisa Page, his mistress who also worked on the Mueller team, mar his work on both of those investigations. Democrats are downplaying the exchanges and accusing Republicans of hyping texts in order to protect Trump from Mueller. Strzok’s texts do show that he made...