Your responses to last week's SWAT column on active shooter response run the gamut of potential solutions. Make no mistake about it, active shooters pose a threat to society not seen since the sniper era of the '60s and '70s. I'm not talking about political terrorists waiting in the wings to attack America—again.

I'm talking about the lone gunmen who, for their own personal reasons, murder until physically stopped. The result is public fear and terror, and a clamor for police to end this growing threat.

America is a "copycat" nation, with imitation the highest form of flattery.

Some of you may remember the "copycat" tragedies whenever the movie "The Deer Hunter" (a powerful movie about the Vietnam War) was aired. One riveting scene was particularly haunting: the "Russian Roulette" scene. Every time the movie aired, somewhere in America, young males played their own version of "Russian Roulette," with tragic results. It took a number of years, and many tragedies, before this deadly game finally waned.

The active shooter phenomenon has a certain "copycat" quality to it — a deadly game won by causing the highest body count in the shortest amount of time before police can stop them.

Last week's SWAT column was a call for action, and a number of you responded with suggestions, including legally armed citizens defending themselves. The rationale is police can't be everywhere, and can't respond rapidly enough to prevent these shootings.

However well intentioned they may be, America is a long way off from authorizing armed citizens in classrooms. In the meantime, the active shooter problem continues, and police remain the primary line of defense against this threat.

That said, there are steps that can, and should, be taken — right now, today.

Get Citizens Involved

Citizens need to get involved and notify authorities if they learn of potential threats. Citizens are our "eyes and ears," our early warning system who alert police and security to deadly threats. This system has already proven effective in high schools and middle schools.

Next is for college campuses, shopping malls, churches, etc. (wherever large gatherings of people occur) to target harden their facilities to make it harder for shooters to gain access to their intended victims. Again, high, middle, and elementary schools have led the way through closed campuses and lockdowns. Schools at all levels have also increased armed security presence, an effective form of target hardening.

College campuses are more like small cities—with spread out campuses, numerous buildings, students, faculty, and visitors—making them difficult to close or lockdown. Even so, many colleges have instituted their form of lockdown and notification of trouble, along with armed campus police or security, resulting in improved target hardening.

Carry Off Duty

The next counter-measure is one that LTC Dave Grossman has been preaching to law enforcement for years. He says if you are legally authorized to carry your firearm, you have a duty to carry it—on and off duty. To emphasize his point, he cites horror stories of unarmed officers who have found themselves in the middle of deadly force situations.

There are many examples of off-duty armed officers being at the right place and time, preventing further shooting tragedies. One that readily comes to mind is the 2006 Salt Lake City mall active shooter. He was interrupted by an armed off-duty officer who diverted the shooter's attention away from his intended victims long enough for Salt Lake City Police to take over.

With the passage of H.R. 218 into federal law, all qualified active and retired law enforcement are legally authorized to carry firearms (with certain restrictions). There are more than one million legally authorized, trained, armed law enforcement officers in America who, by their sworn oath are duty bound to protect the lives of the innocent. Imagine the surprise of the active shooter in Salt Lake City facing the armed response of that off-duty police officer.

First Responder Response

The next counter-measure, adopted in the wake of Columbine, is first responder response to active shooters. This tactic has dramatically improved response time and altered active shooter tactics because time is no longer on their side. A growing number of departments are authorizing their SWAT teams to carry their SWAT gear and weapons at all time to ensure rapid, effective response to active shooter incidents.

America has become a test battleground, a deadly "chess game" between active shooters and law enforcement, with America caught in the middle. Perhaps someday (hopefully sooner, not later) a solution will be found. But until then, law enforcement continues to be society's main line of defense against society's threats—including active shooters.

Like lightning, active shooters can strike anywhere, any time, without warning. We need to follow LTC Dave Grossman's sage advice and always be on the alert, armed and ready to protect.