Terrorism can be defined in various ways depending on whose side you are on etc. It is pointless to deny that.

Since we seem to be stuck with the terminology it is understandable that we would define the term in a way that does not include ourself.

Since I (emphasis on I) believe that we (USA) have the overall moral high ground in this war and any war faught in my lifetime, I choose to and I believe I am right to define terrorism in a way that does not include anything our government has sanctioned in my lifetime.

If I were a diplomat, I might spend more time agonizing about this. Being who I am, I do not feel compelled to feel guilt or ambiguity for what we have done over the course of building the world's greatest nation.