Special counsel Robert Mueller is facing new problems as multiple intelligence agency whistleblowers and former underlings accuse him of overseeing and covering up massive off-the-books surveillance activities during his tenure as director of the FBI. A former FBI special agent accuses Mueller of lying to the Senate Select Committee on Intelligence regarding the scope of his surveillance programs. Another NSA and CIA whistleblower accuses Mueller of overseeing a secretive program that surveilled President Donald Trump while Trump was a private citizen — an accusation that is already being heard in court. Another whistleblower claims that former FBI agents would testify...