All rifles combined, not just assault rifles, are virtually irrelevant in homicide statistics, and many of those used are by drug cartels (sometimes armed by the branch of the federal government charged with enforcing gun laws). More people are murdered with clubs and hammers than rifles, and about twice as many are killed with bare hands. About four times as many are murdered with sharp pointing things, and five times as many are killed with "other weapons" (probably frozen turkeys). More people are also murdered with shotguns than all rifle types combined.
There are thousands of children killed every year at the hands of adults. It is VERY unfortunate and there's little we can do to stop it. Often the warning signs are not there until the crime is ultimately committed.
So yes, there are more homicides committed by other means. But it's not about the overall quantity of deaths that the ban concerns. It's about the number of deaths in a single incident
. Most homicides involve people who know each other. But when a death is caused at random, no "personal cause" at hand, it angers people the most. These assault weapons make it very easy to just kill a bunch of people all at once. It empowers the killer to murder many at will. THIS is what the ban is all about. Because if we don't do anything to stop it, the fear (and right so), is that more people will seek to do the same thing. Troubled, desperate people who see this as an effective means to vent their anger.