Federal investigators have arrested a 21-year-old Air National Guardsman in connection with the alleged leak of classified U.S. intelligence documents. WSJ’s Sadie Gurman discusses what we know about the documents, the arrest, and what could be next. Further Reading: -Air Guardsman Arrested in Connection With Leaked Documents  -U.S. Investigation Into Leak of Classified Pentagon Documents Focuses on Insiders  Learn more about your ad choices. Visit megaphone.fm/adchoices