On Nov. 29, three ordinary citizens’ immediate response to a knife-wielding terrorist on London Bridge got me thinking. What about? The citizens set aside concerns about their own safety and focused on occupying the terrorist until police arrived. This reminded me of a teacher I know.

Why? Because she’d encountered a middle school student on a rampage. She literally ran into him as he pushed students aside in his rush to leave the school, and he slammed her against the lockers as he passed by.

Shaken but uninjured, she told the boy to stop, and when he didn’t, she wrestled him against the lockers until he calmed down enough to be taken to the principal’s office.

“How,” I asked her, “did you take on an out-of-control boy your size who might have a knife? Weren’t you concerned for your own safety?”

“Because,” she responded, “he might have hurt other kids. And, besides, what was the alternative?”

She was right. Any lesser response risked the other kids’ safety and emboldened the boy’s disregard for others. Better he should suffer consequences now and learn outrageous behavior ends in disciplinary action.

Where did she learn this? At home. She came from three generations of teachers, almost all women, who put their students’ and colleagues’ safety before their own. How did this happen? Everyone learned growing up that if someone else was in danger, you stepped in and did what you could to help.

Indeed, the teacher’s niece, at age 6, sat on the school bus with a developmentally delayed 9-year-old girl. Then one day her school bus came home late.

When it arrived, the bus driver explained to her mom that some sixth-grade boys on the bus had been teasing her daughter’s friend about her disability.

The daughter, upset at the boys’ teasing, walked to where they sat, put her hands on her hips and declared, “You can’t do that to her! She’s my friend!”

The bus driver said the boys stopped their teasing and talked quietly the rest of the trip.

When I asked Mom if she was concerned that the boys might bother her daughter, she looked at me and asked, “What else could my daughter do? She took a stand on the boys’ hurtful behavior.”

As with the middle school boy, doing nothing would tell the sixth-grade boys their behavior was acceptable and/or unnoticed while calling them on what they’d done held them up to scrutiny by other kids. Bad behavior, they learned, has consequences.

The 6-year-old’s efforts didn’t result in a confrontation with the boys because not all inappropriateness results in violence.

Another member of that family, who is 6-foot-3 and 220 pounds, attended a community college. And after class on Fridays, he went out for beer with his buddies. On one occasion, a very large man (he called him “a Viking”), came up to him at the bar and bumped him with his shoulder. He moved over and the Viking did so, too, bumping him again.

The man turned to the Viking, smiled, and said, “if you want to fight, that’s fine. But you’re gonna have to send out for a pizza.”

“A pizza? Why?” the Viking asked, perplexed.

“‘Cause you’re gonna be here all night,” was the answer.

The Viking grunted, hesitated, and walked away. Why? Because what he’d heard caught him off guard and his original intentions vanished.

These examples all featured different kinds of aggressive acts. The teacher held the student in one place until he calmed down, the 6-year-old confronted the offending boys, and the man distracted the Viking -- and these contrast with the actions taken by the three Londoners. There are, in short, many ways of dealing with unacceptable behavior.

In all these cases, people were prepared to intervene when someone else was threatened because doing so was the right thing to do. The only question I have is whether I have the temerity to do the same if I see someone being threatened. I surely hope so.

And you? What would you do?

Hank Slotnick is a retired UND professor who, with his wife, winters in Pima, Ariz., and summers in Debs.