I do not want to be like the parents I saw waiting during a lockdown Thursday at one of the Philadelphia suburbs' biggest high schools.

I do not want to imagine, as I have been imagining with increasing anxiety over the last few months, that my young boys will one day be texting me, or their dad, while barricaded against an active shooter or, as was the case at Upper Darby, a classmate spotted with a gun.

This is my parental screed: We cannot accept gun massacres and gun-toting hotheads in schools as an inevitable likelihood. Tell me you agree — all of you who are raising kids in this terrifying new American age.

We must fight. We must not let cynical politicians and lobbyists-force feed us a story line that mass killings by gunmen are part of the First World Order, and that it's our job to suck it up in the name of the Second Amendment. That the only solution is to fill the schools with gun-armed teachers as a line of defense.

This is how barbarians take down a civilization — when its people stop fighting for civilized norms.

For me, the first too-close-for-comfort moment came a few weeks ago. I got a letter in my inbox about a planned lockdown drill at my son's elementary school. I was grateful, on the one hand, to hear that his district — not Upper Darby — was proactive. But I also was speechless as I read the email from administrators.

I kept picturing my boy taking a break from learning to write lower-case letters so that he could practice hiding from a madman with an AK-47.

Then, came the Twitter blast that sent me into journalist action Thursday morning: Someone inside Upper Darby High School had a gun and the place was on lockdown.

This was my alma mater. It is a hub of humanity, a melting pot teeming with 3,700 students on Lansdowne Avenue in eastern Delaware County.

I rushed to the scene and parked in a cemetery across the street. There were cop cars everywhere. Parents clustered on baseball fields and in front of the Performing Arts Center that is home to the nationally known Summer Stage theater program. It was surreal.

Students were locked in classrooms as police and school officials scoured video footage for a student who had been spotted with a gun.

I ran into a dad. He told me he had been texting with his twin boys inside.

"Dad, I'm scared," he said one son wrote to him, followed by: "I want to know what's going on."

"Don't worry," he said he wrote back. "Stay where you are. Keep your head down. I'm here."

Then, the 49-year-old Lansdowne native, who refused to give me his name, said he texted words of reassurance: "I told them both, 'You're going home.' "

The man, who now lives in Secane, had just rushed to the high school from his job in Philadelphia.

"I'm in shock," he said, and we parted ways.

Police Chief Mike Chitwood said a 16-year-old had been detained. A kid found with a plastic toy version of a .45-caliber handgun "in his crotch." Acting Superintendent of Schools Daniel McGarry stood by Chitwood's side. Social workers and grief counselors were on their way. I listened to both men in a hallway I had walked through many times as a teen.

McGarry is angling to perhaps add metal detectors to the school but isn't sure parents will support it. Just last month, he said, parents nixed a proposal to arm all 40 security guards at district schools, for fear that it would lead to a surge in student arrests.

"The public did not want that to happen," McGarry told me.

I then pulled Chitwood aside. Tell me, I said to the grizzled Philly PD veteran, why I — why any parent — should accept all of this insanity as a part of life that's here to stay in the USA. He didn't push back one bit.

Back in the 1950s, they had drills at Chitwood's South Philly grade school. He still remembers ducking under his desk — as though this would somehow protect anyone in the event of a nuclear attack by the Russians. But what's happening in 2018 with guns? It's like nothing Chitwood has ever seen.

"I have been a cop for 55 years," he said. "The easy accessibility of guns. … It's a truly sad commentary on society."

Watch it, Chief, I warned. The NRA might brand you a bad guy.

"I could care less," he snapped back.

We should all share his outrage. Without stricter gun laws, the barbarians win. And our children are stuck with the uncivilized mess we leave behind.