He was stating facts about people who were conducting a holy war against us. Not praising, not glorifying. Just stating facts about people who, although it is sick and perverted, were willing to die for their cause and their god. I don't believe that the killers at Columbine believed that they were in any kind of war or in a hurry to meet any god. They cowardly attacked defenseless kids and then killed themselves to avoid the legal consequences of their acts.
The subtle difference is that in the case of the terrorists, there will be more attacks of one kind of another in some coordinated fashion and that is what makes it a war. The random and uncoordinated school shootings are the work of sick individuals looking for their 15 minutes of fame.