There are some things we should never have to worry about.

For instance, we should never have to worry about being in traffic and someone firing a gun from a passing vehicle.

When we send our kids to school, we should not have to worry about mass school shootings.

And it should never cross our minds that a “personality conflict” at work could become the next “workplace tragedy.”

But unfortunately, many of us do worry about all these things, primarily because too many of our political leaders still can’t see the merits of commonsense gun control measures.

OPINION

Meanwhile, we have a new worry.

On Sunday afternoon, a woman was pushed from an L platform onto the tracks at the CTA Red Line Belmont station, and no one has been apprehended.

It was the second time in a little more than a month that this has happened.

On April 30, another woman was walking along the platform after exiting a Blue Line train at Western and a man ran up and pushed her onto the tracks.

Take a look at the surveillance image of the suspects in the two most recent assault cases. These men are still walking around our streets and that makes us targets for their insanity. If you think you know either of these men, don’t hesitate to contact the Chicago Police Department. | Photo courtesy of WGN

Who could do such an evil thing except someone with a mental problem?

Those of us who grew up taking public transportation to get around the city know the dangers of the deadly “third rail.”

So the horror of having a stranger push you over the edge of the L platform is unimaginable.

Yet it has happened at least four times recently.

In March, Wilma Maxey pushed a stranger onto the CTA Red Line tracks at the Morse stop, allegedly because she was “upset” and wanted to “kill” someone.

Maxey is believed to be mentally ill, and was still sitting on a bench when police arrived.

Chad Estep, 34, was charged in October 2017 with attempted first-degree murder for pushing a male commuter onto the CTA Blue Line tracks last August.

Estep, a data analyst, with a Ph.D. in neuroscience from Northwestern University, didn’t know the victim, and apparently, there was not a confrontation before the push.

Police have credited tips from the public with leading them to Estep.

They have similarly distributed surveillance images of the suspects in the two recent incidents.

The police described both suspects as a “black man between 35 and 50 years old.”

All of these attacks are horrifying.

But what makes Sunday’s assault especially heinous is the 48-year-old female victim was pushed after she confronted a man who was “publicly urinating“ on the tracks.

I’m not suggesting a woman ever put herself in danger by confronting a stranger about inappropriate or criminal behavior.

But there are signs all over the city that advise us to “say something,” if we “see something.”

We are being asked to report all sorts of suspicious behavior, including reporting criminal activity in the neighborhoods, all with the goal of making Chicago a safer city.

The unidentified victim in Sunday’s assault did what she thought was the right thing to do. She confronted a situation that most would find repugnant.

Now she is in serious condition at Illinois Masonic Medical Center.

She is in my prayers and hopefully in yours, and I hope the Chicago City Council honors her for her courage when she recovers.

Meanwhile, take a look at the surveillance image of the suspects in the two most recent assault cases.

These men are still walking around our streets and that makes us targets for their insanity.

If you think you know either of these men, don’t hesitate to contact the Chicago Police Department.

The suspects didn’t commit these assaults because they needed money for drugs. They didn’t do it to get their hands on a cellphone. They did it because they could.

We need to help get them off the street before this depravity becomes a trend.

Mary Mitchell and educator Leslie Baldacci are co-hosts of a podcast on race relations called “Zebra Sisters.” Check out the first season on iTunes and Google Play Music — or find individual episodes on the Sun-Times’ Zebra Sisters page. Email Mary and Leslie at zebrasisters@suntimes.com or suggest topics for season two by calling the Zebra Hotline: (312) 321-3000, ext. ZBRA (9272).