Maj. Nidal Malik Hasan was declared "not a terrorist" before the facts were out - even before officials were sure whether the attacker was alive or dead. Failing to honestly name a terrorist attack despite the evidence is as destructive and dishonest as leaping to call an attack terrorism without the facts to support that.
Apparently, the claim was based largely on the fact that Maj. Hasan appears to have been a lone gunman. However, terrorism is defined not by the number of people involved, but by the motivations and intentions of the attacker. If reports about him are true, Maj. Hasan clearly was a terrorist.