The part I do not get. If it is only a half-mile to a mile across campus, where was the shooter between the first killing and the spree on the other side of the campus. Most people could crawl a mile on their belly in three hours with plenty of time to spare, so where did he go what did he do for that time?
Or are we looking at separate and not quite coordinated events? Opportunistic Mayhem?
This reeks of planning, forethought, and deliberate execution.
It appears vulenrabilities were studied and taken advantage of, and it is safe to assume that there will be others studying the reaction, any security enhancements, and likely policy reviews conducted on campuses nationwide for similar weaknesses which can be exploited.
Whether this is the vangaurd of jihadi attacks on American schools or not, the lurking jihadis will be studying every reaction for flaws. They have promised to bring Beslan-type slaughter here.