Why is administration allergic to using words, "terrorist attack"?

Donald R. McClarey reports: "Outraged victims and the families of the slain of the murderous rampage of Major Nidal Hassan at Fort Hood in 2009 have created the video [below] attacking the Obama’s administration’s denial that this was a blatant act of terrorism and labeling it work place violence." Here's the video, and it's heartbreaking:

Ed Morrissey writes (Hot Air, October 19, 2012):

Help me understand this. Nidal Hasan has been held for almost three years after shouting “Allahu akbar!” and opening fire on fellow soldiers at Fort Hood, killing 14 and wounding several others. Almost immediately, evidence arose that Hasan had been in contact with the late and unlamented al-Qaeda leader Anwar al-Awlaki to discuss the legitimacy of conducting jihad within the American military, a scandal that prompted questions about why the military hadn’t intervened prior to the massacre. Most people assumed that was enough to consider the massacre a terrorist attack, including me.

Apparently not, however, according to Stars and Stripes. The Obama administration has thus far refused to consider the November 2009 mass murder a terrorist attack, choosing instead to call it — I kid you not — “workplace violence.”