On this date in 1987, a once-promising American intelligence asset was executed with a single gunshot to the head in Moscow — his treachery exposed by two of the most infamous Soviet moles in U.S. intelligence history. A Lieutenant Colonel in the KGB posted to the Soviets’ official Washington, D.C. offices in 1980, Martynov had turned in 1982 and begun funneling intelligence to the CIA and FBI under the cryptonym “Gentile”. Truth be told, he was a mediocre source, but he was a younger officer with the chance to grow into a more important asset in the years ahead. Fate...