"semi- and fully-automatic rifles are offensive weapons"
"[Automatic weapons'] only real purpose is to kill lots of people in the shortest time possible."
"support a total ban on possession of all types of automatic weapons"

Do references to "automatic weapons" in the last two quotes also refer to "semi-automatic" weapons as in the first quote?

If so, how does the letter writer explain the possession and use of both full- and semi-automatic weapons by law enforcement? Is killing lots of people in the shortest time possible part of the job description? Or is it conceivable that "defense of self and others" is a legitimate purpose of such weapons?

If the writer is advocating a total ban on both semi- and fully-automatic weapons, would he have us all revert to revolvers and (at best) lever-action rifles? That is, no firearms advances since the mid 19th century?