Yesterday’s news became big news on the Fox News Channel last week when former New York City Mayor Rudolph Giuliani brought up the name of President Barack Obama’s childhood mentor, Frank Marshall Davis. It was almost seven years to the day when we published our seminal piece about Davis, “Obama’s Communist Mentor.” Davis was a member of the Communist Party and a suspected Soviet espionage agent. He was included in the FBI’s security index, meaning that Davis could be arrested or detained in the event of a national emergency. The FBI file on Davis documents his anti-white and pro-Soviet views,...