An odd question, how often do criminals choose to rob gun stores that are owned/staffed by war veterans?
Part of the protection the gun store has is the expectation that he has a weapon under the counter that will likely tear someone in two, and the other part of the protection is that it is likely that people who shop at the store are much more likely to be armed and take offence to you trying to rob the place. When the odds that your crime will be stumbled across by an armed individual goes up the likelihood of committing that crime goes way down, which is why gun-crime tends to go down in places that institute laws allowing concealed weapons to be carried.
Much like healthcare debates, gun crime is a problem where people never really argue about how to actually address the root causes which is why there is rarely any improvement. Most career criminals have records that date back to their early teens, and usually involve several arrests for more minor crimes prior to becoming adults. A debate over how you reduce the recidivism rate of young offenders in half or quarter is long over-due in the United States, and every small victory on that today will result in big benefits down the road.