Police and other law enforcement officers carry semi-automatic handguns and rifles, as they might come across some really bad people. None would dream of demanding that a police officer give up his or her weapon. The same logic that says these individuals need access to semi-automatic weapons equally applies to the "average" citizen, as the dangers are the same; you never know when you might be set upon by a truly criminal and deadly threat. I know this logic does not compute in New York (where you aren't trusted with a large soda) or San Francisco (where you aren't trusted with goldfish), but it should be common sense elsewhere.
If an adult cannot be trusted to act responsibly, then we have courts to deal with those problems on an individual basis. We should not penalize everyone for the criminal actions taken by fewer than 1 in 100,000,000 individuals (mass murderers) each year.
The Second Amendment has nothing to do with what sort of gun you might use for hunting or target shooting. The second amendment gives "the people" the right to bear arms.John Dawson