Two elementary school students and a female teacher were shot in Townville Elementary School in Townville, South Carolina today.

All three of them are expected to survive. The teenaged suspect was arrested at the school. The suspect is believed to have murdered his father at a home on a dead-end gravel road 3.5 miles away prior to the school attack.

It shouldn’t have been possible.

After the massacre at Sandy Hook Elementary in Newtown, Connecticut in 2012, the National Rifle Association (NRA) formally proposed the National School Shield Program.

The goal of the National School Shield program was to answer a simple question:

How do we best protect our children?

The NRA’s recommendation was to afford our children the same sort of protection that gun control advocates and politicians afford themselves: trained, armed security.

In specific, the NRA called for armed school resource officers (SROs) to be deployed to all schools in the United States.

SROs—primarily sworn law enforcement officers such as Sheriff’s deputies or police officers—are already common in high schools across the country, and have stopped mass murders from occurring at least twice in recent years.

• Almost exactly a year after Sandy Hook, an armed SRO cornered a would-be mass shooter at Arapahoe High School in Centennial, Colorado. The gunman, who had a hit list, a shotgun, 125 rounds of ammunition, and three Molotov cocktails, committed suicide as the deputy closed in on him. Because of the school SRO, the attack was over inside 80 seconds.
• Reynolds High School in Troutdale, Oregon, employs multiple on-campus SROs. In June of 2014, two of them engaged a would-be mass-murderer armed with a stolen AR-15 and 9 30-round magazines inside of a minute and forced him to take cover in a bathroom, where he took his life.

Just one month prior to the Reynolds High School Shooting, Purdue University’s Homeland Security Institute announced that their research showed a combination of having armed SROs (school resource officers) and armed faculty/staff/teachers in school reduced response times to active shoots dramatically, and lessoned casualties by two-thirds.

In a typical mass shooting scenario, a person is shot every 20 seconds. In an elementary school, where small children have nowhere to run and are too small to easily escape, the carnage can be much worse, much faster.

Even a relatively fast response time of five minutes gave the Sandy Hook shooter enough time to shoot 20 children and six adults. Most of the victims were shot repeatedly.

As Eric Rawls so critically asked three long years ago:

What society in human history ever gathered its children together, then issued a public guarantee that they would be left completely undefended?

How much longer will we sit by as this invitation to slaughter the most vulnerable members of our society is repeatedly accepted?

How much longer, indeed?

It didn’t change after Newtown.

Will it change after Townville, or must we learn much harsher lessons on the order of a Day of Wrath or a Beslan School Massacre, with hundreds of dead, before we seriously begin defending our children?