I'm trying to be careful about using the words terror, terrorism, and so forth.
For example, regarding the recent beheading of the Brit soldier, the word terrorists was used extensively. I fell right into using it myself. A little ways into the thread, a poster pointed out that it wasn't terrorism because the killers attacked a soldier--the military. Whoa! He was right. Moreover, the killers didn't attack the civilians in the immediate area. A woman was even able to stand dangerously close to one of them videoing his rant. That wasn't terrorism. If anything it was a very small scale insurgent attack.
In the Santa Monica killings, I've not yet seen a political demand, something that is included in the definition of terrorism. And, don't let anybody claim the definition is changed--they're just looking for sensationalism or advancing an agenda. Terrorism has always included some political demand like "get out of the West Bank and Gaza."
Slopping the meaning of terror over onto non-terror acts feeds government power. Tons of civil protections are being sacrificed in the name of preventing "terror". Also, its gotten to the point where I've read several times of people being prosecuted for making everyday threats against others as "terroristic threats."