Despite this breakdown, I feel relieved Army did not know before. I could not comprehend. -- Pentagon Only Learned of Hasan's Emails After Killings

From The Wall Street Journal:

The Pentagon said it was never notified by U.S. intelligence agencies that they had intercepted emails between the alleged Fort Hood shooter and an extremist imam until after last week's bloody assaults, raising new questions about whether the government could have helped prevent the attack.

A top defense official said federal investigators didn't tell the Pentagon they were looking into months of contacts between Maj. Nidal Malik Hasan and Anwar al-Awlaki. The imam knew three of the Sept. 11 hijackers and hailed Maj. Hasan as a "hero" after the shooting last week at Fort Hood that left 13 people dead.

"Based on what we know now, neither the United States Army nor any other organization within the Department of Defense knew of Maj. Hasan's contacts with any Muslim extremists," the official said.

The Pentagon comments fueled a growing dispute among various branches of the government about whether Maj. Hasan should have been more deeply investigated before he allegedly walked into a crowded soldier-readiness center at Fort Hood and opened fire.

A person familiar with the matter said a Pentagon worker on a terrorism task force overseen by the Federal Bureau of Investigation was told about the intercepted emails several months ago. But members of terror task forces aren't allowed to share such information with their agencies, unless they get permission from the FBI, which leads the task forces.

In this case, the Pentagon worker, an employee from the Defense Criminal Investigative Service, helped make the assessment that Maj. Hasan wasn't a threat, and the FBI's "procedures for sharing the information were never used," said the person familiar with the matter.