What the evidence shows
The Washington Post reported that an FBI-led task force obtained Hasan's emails with Anwar al-Awlaki between late 2008 and June 2009 and did not forward them to the military before the Nov. 5, 2009 Fort Hood shooting. The FBI did assess the messages; investigators concluded they posed no threat and treated them as research, so the government was not inactive.
Los Angeles Timeslatimes.com
Washington Postwashingtonpost.com