It the wake of the attack on unarmed innocents at Marjory Stoneman Douglas High School, it is important to remember that President Trump campaigned on allowing teachers to be armed for self-defense.

He first broached the subject after the October 1, 2015, attack on Umpqua Community College (UCC); an attack in which an armed man entered a gun-free campus and killed nine people. Trump responded to the attack by saying, ““I’ll tell you, if you had a couple of the teachers or someone with guns in that room, you would have been a hell of a lot better off.”

Weeks later, during the October 28, 2015, presidential debate, Trump revisited the topic by stressing that gun-free zones actually attract attackers who might avoid campus if they knew their would-be victims could shoot back. He said gun-free zones provide “target practice for sickos.”

Two months later, on October 8, 2016, The Washington Post quoted Trump saying, “I will get rid of gun-free zones on schools.”

The left went apoplectic over the suggestion that teachers should be armed to defend their lives and the lives of their children. Sen. Chris Murphy (C-CT), called the idea “sinister” and said Trump was only suggesting it because it was part of “doing the bidding of the gun lobby.” These are strange words when one considers that Murphy is a Senator from a state where 26 innocents were gunned down in a gun-free zone (Sandy Hook); a zone where the law-abiding teachers and staff were prohibited from having guns with which to shoot back if under attack.

Of course, Hillary Clinton recoiled at Trump’s idea of allowing teachers to carry guns for self-defense. After all her lamentations over school shootings and attacks on innocents in other gun-free zones TIME quoted her saying that arming teachers “[is] no way to keep us safe.”

For leftists like Sen. Murphy and Hillary Clinton, the solution is always more gun control, which means more the very laws that are failing to stop attackers now. In rare cases a leftist will even voice support for more armed school resource officers, but Marjory Stoneman Douglas High had an armed officer on campus at the time of the attack and the shooter simply circumvented him. And once the shooter avoided detection by that lone officer he could be confident that no one else could offer armed resistance.

Is this the left’s way to keep us safe? If it is, it is not working.

There must be layers of defense. as Police One’s Mike Wood explains, that those layers include an exterior, comprised of armed resource officers, and an interior, comprised of teachers (and staff) who have concealed carry licenses and have met their state’s training standard to carry in school. Without the latter, attackers who are sly enough to make it onto campus are literally unstoppable.

It was difficult to argue against Trump’s assessment that some of the teachers at Umpqua Community College should have been armed and it is even harder to argue with it now.

He campaigned on removing the prohibitions against teachers being armed for self-defense. We are waiting for the fulfillment of that promise.

It is inhumane to demand that educators likewise be sitting ducks.

AWR Hawkins is an award-winning Second Amendment columnist for Breitbart News, the host of the Breitbart podcast Bullets with AWR Hawkins, and the writer/curator of Down Range with AWR Hawkins, a weekly newsletter focused on all things Second Amendment, also for Breitbart News. He is the political analyst for Armed American Radio. Follow him on Twitter: @AWRHawkins. Reach him directly at awrhawkins@breitbart.com. Sign up to get Down Range at breitbart.com/downrange.