What is the difference between a "spree killer" and a "terrorist"?

This question comes directly from this article by Tim Kreider and I think it is a worthy topic of discussion; particularly considering what is happening in D.C. at this time.
What are your thoughts?
What makes the difference between the two, is it the presence of a Koran in the hands of one?
Is it where and/or how it is accomplished?
Do you agree with Mr. Kreiders final paragraph: ”.... sometimes it’s hard to resist an even darker suspicion: that the crucial difference between what we call “spree killers” and “terrorists” isn’t race or ideology or armament, or even the power and influence of the pro-shooter lobby, but that our government, photo-op condolence hugs aside, is ultimately indifferent to attacks on its people — even on its children — but reacts with instant Draconian hysteria to any attack on its authority.”?