I honestly believe that persons like Costas and Whitlock really do fear irrational, irresponsible behavior with firearms. Based on the juvenile, irresponsible, low self control manner which some persons exhibit.
The worst part of that though, is that they are largely judging human nature, by basing it on the inner feelings and uncontrolled emotions of the person they know best, themselves.
"No free man shall ever be debarred the use of arms."- Thomas Jefferson