MSNBC host Andrea Mitchell fretted Friday that the FBI's acknowledged error in not following up on a credible trip on Nikolas Cruz might serve as fodder for critics of the Russia investigation. In a statement, the FBI said Friday that "protocols were not followed" after someone contacted the bureau's Public Access Line on Jan. 5 with concerns about Cruz, who authorities say confessed to carrying out the Florida school shooting this week. The individual provided information in January about Cruz's desire to kill people, erratic behavior, disturbing social media posts, and potential to carry out a school shooting. The FBI...