Last week, a man with a gun killed four Marines, mortally wounded a Navy sailor, and injured a police officer in Chattanooga, Tennessee. And last night, in Lafayette, Louisiana, another man with a gun shot into a movie theater, killing two people and injuring nine more before turning the weapon on himself.

Both tragedies felt like a punch in the gut. Today is especially hard for survivors and victims’ families from the Aurora theater mass shooting three years ago, who are just finishing up the trial for the accused killer of their loved ones. It’s past time to stand with all victims and survivors of gun violence and say – in the words of Richard Martinez, whose son, Chris, was killed in the Isla Vista shootings last year – that “not one more” person should be sacrificed to such senseless killing.

RELATED: 3 killed, 9 wounded in movie theater shooting

For my family, the mass shooting in Chattanooga hit particularly close to home. As a Pentagon 9/11 veteran myself, I know our men and women in uniform put their lives on the line wherever they are every day, but it’s especially tragic when they’re caught in the line of fire here at home. My thoughts and prayers go out to their families, their comrades, and their community.

Close video Aurora victim’s parents: ‘You wonder how this can continue in our country’ The theater shooting in Lafayette, Louisiana comes three years after James Holmes shot and killed 12 people and wounded 70 others in a movie theater in Aurora, Colorado. Sandy and Lonnie Phillips, whose daughter Jessica Ghawi was among those killed in Aur The theater shooting in Lafayette, Louisiana comes three years after James Holmes shot and killed 12 people and wounded 70 others in a movie theater in Aurora, Colorado. Sandy and Lonnie Phillips, whose daughter Jessica Ghawi was among those killed in Aur share tweet email Embed

Now it’s routine for gun lobby commentators and politicians to blame mass shootings on the existence of so-called “gun-free zones.” This is a red herring, pushed by the gun lobby to advance a “guns everywhere” agenda, which insults the dead and mocks the living by reducing tragedy to a mere trope.

It’s past time to lay this fallacy to rest.

In our case, Virginia Tech had routine police presence in and around campus, which the gunman even accounted for in his planning. It’s pointless to debate what hypothetically could have happened if a student or teacher carried a concealed firearm in Norris Hall that day, because nobody will ever know. But such a debate misses the main point: Mary, and everyone else, would have been far safer if the shooter had been unable to obtain a gun in the first place.

In Chattanooga, everyone at the recruiting center, the first attack scene, survived despite a hail of rapid long gun fire, because the combat veterans present followed their active shooter training and helped others to shelter and to evacuate the building. In their case, effective training and quick thinking, not the presence of a gun, made the difference. Only time will tell what exactly happened at the second scene, but official accounts so far indicate our service members’ brave actions and teamwork probably saved lives.

“So-called ‘gun-free zones’ are not the problem, and victim-blaming is not a solution.” Everytown for Gun Safety. Many of these shootings relate to domestic violence, and more than half the victims of mass shootings are women. Many of these mass shootings never grab national headlines. You may not know this, but a mass shooting that killed two adults and two teenagers, and left an eight-year-old boy fighting for his life, happened just this month in a private home in Holly Hill, South Carolina.

So-called “gun-free zones” are not the problem, and victim-blaming is not a solution. Dangerous people’s continued access to guns is the problem, largely due to the gun lobby’s extreme agenda which harms everyone, including law-abiding gun owners, military members, and law enforcement. So let’s work on the real problem, together.

The solution is to strengthen our common-sense gun violence prevention laws, like legislation pending in Congress right now to ensure background checks occur on all gun sales. It won’t prevent every tragedy – nothing will – but it would go a long way toward making Americans safer.

Peter Read is a retired Air Force Lieutenant Colonel. His daughter, Mary, was one of 32 students and faculty killed in the Virginia Tech shooting on April 16, 2007.