The casualties of a mass shooting are not only those killed or wounded in the burst of gunfire. The damage reverberates, often for years, sometimes magnifying a family’s tragedy.

Sadly, this country has borne witness to that awful truth many times. And we are reeling once again, this time from the recent news that three people connected to two of our worst national nightmares took their own lives.

Two were students at Marjory Stoneman Douglas High School in Parkland, Fla., where 17 people were killed last year on Valentine’s Day. One, a 16-year-old boy who had not been identified at the time of this writing, was a current student and a ninth-grader at the time of the shooting. The other, 19-year-old Sydney Aiello, was a 2018 graduate who was diagnosed with post-traumatic stress disorder and was struggling with survivor’s guilt after one of her best friends, Meadow Pollack, was slaughtered.

Recently, Jeremy Richman, the father of a first-grader killed in the 2012 massacre of 26 people at Sandy Hook Elementary School in Newtown, Conn., was found dead in an apparent suicide in the building that housed a program he founded to support research on brain abnormalities linked to violent behavior. Richman, a neuropharmacologist who had two other small children, spoke a short time earlier about research on identifying symptoms of people in crisis in a summit at Florida Atlantic University, a short distance from Parkland.

Despite the immeasurable heartache, Congress still refuses to pass sensible gun control legislation. But last Tuesday, the Republican-controlled Senate did finally hold a gun control hearing. The Judiciary Committee heard testimony about “red flag” laws that define under what circumstances authorities can confiscate guns from people deemed to be risks to themselves or others. The alleged Parkland gunman fell into that category.

Committee chairman Lindsey Graham said Congress should be able to pass legislation to incentivize states to pass red flag laws, which have been adopted in 14 states. Unfortunately, Graham ruled out federal red flag legislation, which would be far more effective.

Nor is the Senate likely to pass a bill approved in the House to mandate background checks on all gun sales, a measure backed by the vast majority of Americans. That’s distressing; New Zealand banned automatic weapons six days after 50 people were killed in attacks on two mosques there last month.

The only bright spot is that President Donald Trump’s new regulation banning bump stocks — which enable rapid firing of semiautomatic guns and were used by the Las Vegas gunman to kill 59 people in 2017 — did take effect despite gun-rights activists’ attempts to seek court injunctions.

So we muddle along — overwhelmed by the endless tragedy of gun violence, angered by the shameful lack of action in Congress to do anything about it.

Newsday