via Mother Jones:
Hasan first appeared on the bureau’s radar in December of 2008—nearly a year before the Fort Hood massacre—when he emailed Awlaki to ask him whether serving in the US military was compatible with the Muslim faith. He also asked whether Awlaki considered those who died attacking their fellow soldiers “shaheeds,” or martyrs.
At the time, Awlaki, who was killed by a US drone strike in 2011, was emerging as Al Qaeda’s chief English-speaking propagandist. He was also known to have ties to several of the 9/11 hijackers, two of whom attended his mosque in San Diego.
The FBI’s Joint Terrorism Task Force in San Diego, which was tracking Awlaki, intercepted Hasan’s December email, along with another sent in January. A search of the Pentagon’s personnel database turned up a man named Nidal Hasan who was on active military duty and was listed as a “Comm Officer” at Walter Reed Army Medical Center in Washington, DC.