In a more perfect world, we would not know the name Kendrick Castillo. In a more perfect world, the only son of John and Maria Castillo would be starting a career in robotics after graduating college, driving his jeep all over, attending church with his parents, maybe spending time with someone he met and was sweet on, and generally living the promising life of a man in his early 20s.

But our world is less perfect.

May 7, 2019 — five years ago almost to the day — in Ms. Harper’s British Lit class just after lunch, two disgruntled students armed with four, fully loaded firearms, entered Classroom 107 of STEM Academy with a plan to murder 28 people. That evil plan failed solely because there were heroes in 107. With the yelled words “nobody f%$#&ing move!” just past the lips of one gunman, Kendrick Castillo — three days from the end of high school — sprung out of his seat and charged him. Immediately behind Kendrick charged Brendan Bialy and Josh Jones. Across the room, Jackson Gregory and teacher Lauren Harper jumped on, fought with, and disarmed the other gunman. Bullets flew everywhere, striking six students (including Jones and Action Jackson) and killing Kendrick feet from where he began class watching “The Princess Bride.”

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In a 30-year career, I have encountered several brave and selfless acts in the face of death, but none as heroic as Kendrick’s and those who attacked their attackers after lunch in 107.

The challenge looking at STEM — or any man-made mass tragedy — in the rear-view mirror is to find a lesson — anything — that lets us feel like we have the ability to prevent evil in the future. Rather than learn from these horrible events, Colorado policymakers used these tragedies to achieve ideological gains instead of pragmatic solutions.

Case-in-point is this year’s spate of Democrat gun-control bills in the legislature. None of them, not the bills to ban guns in “sensitive spaces” (broadly defined as everywhere that is not your basement), to punish those whose guns are stolen from their cars, to restrict concealed-carry permits, or to mandate liability insurance for gun owners, or even the so-called “assault weapon ban,” would have prevented the mass shooting at STEM.

Instead, the legislature’s efforts included more than burdening and punishing lawful gun owners; they extended to efforts to disarm schools entirely by barring trained teachers from carrying firearms in schools who want them to protect their students and faculty. In Colorado, the Democrats’ policy has been to address criminal conduct with firearms by attacking the law-abiding and the firearms themselves. That policy has yet to prove successful.

In my experience, here is what works:

First, the known presence of trained and armed — preferably uniformed — personnel inside places where we congregate and entrust our safety. Mass shooters are cowards by their nature. They want the element of surprise when they attack the unarmed and those they perceive incapable of resisting them. The first, best option is at least one school resource officer (SRO) per school. For districts that cannot afford SROs, armed security or faculty provide a similar deterrent effect and timely response.

Second is timely and decisive action. It matters less who takes the action than that it is taken. In Columbine, our great SWAT operators were kept outside the school while bullets were fired inside. Fourteen years later, when a disgruntled senior student shot Claire Davis at Arapahoe High School, the immediate response by the SROs to run toward the gunfire prevented any further loss of life — except for the gunman. In Uvalde, Texas, law enforcement officers frozen outside of a classroom besieged by a mass shooter only led to more murders of children inside.

At STEM, the immediate action was taken by four students and a teacher who shared a familiarity with the firearms and a commitment to prevent anyone in 107 from being killed by them. One of the lessons we should seek to learn is why those heroes acted that day. What did their parents do to foster such bravery? What experiences did they have that allowed them to fight while others chose flight (as so many would)?

It cannot be overstated how many lives were saved five years ago by the actions of unarmed heroes. One among them made that ultimate sacrifice. Though his parents likely wish they had a less brave son who was with them today, the fact remains they raised a hero. Twenty-seven families thank God everyday for that heroism.

In a more perfect world, we would never forget the name Kendrick Castillo or what he did five years ago.

George Brauchler is the former district attorney for the 18th Judicial District and is a candidate for district attorney in the newly created 23rd Judicial District. He has served as an Owens Early Criminal Justice Fellow at the Common Sense Institute. Follow him on Twitter(X): @GeorgeBrauchler.