Quote: You just answered the question, mass shooters WANT defenseless peoeple to kill. Defenseless, notice the key word. People who have guns are NOT defenseless!
It's only your belief that they only want defenseless people to kill. In both the Fort Hood shooting and the Washington Navy Yard shooting, people there had access to arms. Even in this Florida shooting, the shooter, who was a former student, had to know of the armed guard who regularly worked at the school.
It's very well documented, all that you have to do is look up "Gun-Free Zones.". You just named two locations, very rare.