Senator John McCain ought to be embarrassed. So should House Speaker John Boehner and Congressman Mike Rogers, the former FBI agent who chairs the Select Committee on Intelligence. These pillars of the Republican establishment have been championing the cause of Huma Abedin, the deputy chief of staff to Secretary of State Hillary Clinton. Ms. Abedin’s name arose, along with several others, in connection with questions pressed by five conservative House Republicans regarding Muslim Brotherhood infiltration of the United States government. The GOP establishment, led by McCain, Boehner, and Rogers, has been slamming Congresswoman Michele Bachmann, one of the five House...