Most parents know that when their children want something badly enough, they will do whatever they can to help them get it.

Those impulses aren’t always the best, of course. But recent student protests in the St. Louis area and nationwide are terrific examples of how young persistence can lead to positive change. Now, the protestors must keep their message about gun safety front and center and bring along their parents with them.

The latest demonstrations were touched off by the Valentine’s Day murders of students and others at Marjory Stoneman Douglas High School in Parkland, Fla. At last week’s one-month anniversary of the bloodshed, students throughout the St. Louis area, including at Saul Mirowitz Jewish Community School (see related commentary on opposite page), joined thousands of others from around the world, walking out of class to show their support for tighter gun control. 

Many of the protests lasted for 17 minutes, matching the number of victims in the nation’s latest mass shooting. And the themes of the demonstrations echoed student fears and frustrations that far too little is being done to prevent more such attacks.

Signs with messages such as “Never Again,” “Enough is Enough” and “Am I Next?” brought home the students’ anguish and concern about whether and when still another school shooting may occur.

Particularly poignant were protests at Sandy Hook Elementary School in Newtown, Conn., where 20 children were among 26 people killed in 2012, and at Columbine High School near Denver, where 12 students were among 13 shot to death in 1999. Kaylee Tyner, 16, a junior at Columbine, voiced the feelings of many of the demonstrators when she said:

“We have grown up watching more tragedies occur and continuously asking: Why? Why does this keep happening?”

Good question. One big reason, of course, is the influence that groups such as the National Rifle Association have bought with their contributions to pliable politicians including Sen. Roy Blunt, the Missouri Republican who ranks near the top of the list of recipients of NRA cash.

President Donald Trump appeared to be ready to take on the NRA after the Florida shootings. He even chided some politicians for being afraid of the gun lobby and seemingly backed some stringent but sensible control measures that have been defeated or ignored after past killings.

But Trump quickly backed away from such proposals and has instead pushed the wrongheaded notion that schools will be safer if teachers can be armed. Tell that to the 17-year-old student in California who was injured by debris that lodged in his neck when a teacher, who is a trained police reserve officer, was demonstrating a gun in his classroom last week and it went off accidentally.

When politicians are too timid to challenge the NRA, student pressure may be the most potent weapon in the fight for school safety. No parents want their children afraid to go to class or distracted from learning by fear about what might happen when a gunman begins shooting.

Student enthusiasm and idealism can be a powerful tool. Look at the response at John Burroughs School last week, when representatives of the Westboro Baptist Church brought their despicable brand of hate to mock student Jake Bain, the school’s football star who has come out as gay.

Protesters from Westboro, which is known for its “God Hates Fags” signs and its demonstrations at military funerals, were greatly outnumbered by supporters of Bain. They lined the street with signs proclaiming their solidarity with Jake and their desire for love and inclusion, not hateful, incendiary tactics.

That kind of activism, in favor of tolerance and against wanton gun violence, can be a powerful force. This Saturday’s marches planned in Washington, D.C., and across the United States, including downtown from Union Station to the Arch, will bring that message home once again. Protests planned for next month will do the same.

But demonstrations must be matched with concrete action. Contrary to NRA dogma, the only way to stop a bad guy with a gun is NOT a good guy with a gun. The best way to change bad policy and defeat timid politicians is at the polling place. Elected officials pay attention to public protest. In the wake of the Parkland shooting, the governor of Florida signed a bill to raise the minimum age to purchase a firearm to 21.

High school students who are old enough need to make sure they vote for candidates who favor the policies that their protest signs demand. Students who are not yet 18 can influence their parents to be their proxies at the ballot box and convince them that safe schools result when deadly firearms can’t reach the wrong hands.

That kind of civics lesson is just as valuable as anything that is taught in the classroom. So far, students have shown that they have learned the lesson well. Now, it’s time to keep the pressure on.