Time and time again, we’re told that there’s absolutely no reason to have an AR-15 except to take a human life. They’re “weapons of war,” they’re tools designed to kill and nothing else, some say.

However, an Illinois man is alive today because of an AR-15 in the hands of a private citizen.

Dave Thomas was getting ready for work Monday afternoon when he heard women screaming in his apartment building in Oswego. Thomas, a gun instructor, peeked out the door and saw blood in the hallway. He went to his bedroom, where a handgun and an AR-15 assault-style rifle were lying on the bed. He picked up the rifle. “I teach people how to defend themselves, and it was just a reaction to grab the AR-15,” he said. Police said Thomas confronted a man who was stabbing another man in the apartment complex on the 100 block of Harbor Drive. The man with the knife ran off when Thomas threatened to shoot him. “He was a half a breath away from getting his head blown off and he knew that,” Thomas, 41, said. “That’s why he put the knife down.” … A sheriff’s spokesman, Detective Bryan Harl, credited Thomas with preventing the situation from getting worse, and said the investigation showed he’d done nothing criminal. “He did in the moment what he thought was going to de-escalate this situation and stop any further violence or loss of life and for that he is to be praised,” Harl said.

I think part of why the AR-15 was so effective was because of the media hype. The news is filled with reports of them being instruments of war and murder, so when a man with a knife is faced with certain disintegration from a handheld, small-caliber bazooka, of course, he ran.

If that was the case, the media have finally made themselves useful.

More importantly, though, this was a good guy with a gun at the right place and the right time, something anti-gunners insist almost never happens. Well, it does happen, and this is a prime example.

Further, this one is unlikely to be counted in any statistics, either. The stabbing itself will, but the resolution by an armed citizen may well not be. There’s nothing to report at this point, so it may well slip through the cracks.

And that’s a shame.

Good guys with guns end violent acts by bad people with weapons of all kinds. They end the threat and protect lives. They do it far more often than bad people with guns take lives, and that’s because guns are a lifesaving tool.

Mr. Thomas did the right thing; he put his own safety on the line and protected his fellow man. Contrary to what it may look like from the outside, that’s not an easy thing to do, yet he did it without hesitation. That’s heroism right there, folks.

And think, some people want to disarm Mr. Thomas because of someone else’s misuse of an AR-15.