AMNA NAWAZ: Alarming suicide rates among the military and veterans can be traced to the stress and trauma from the long wars in Afghanistan and Iraq.

But those conflicts are over, and suicides remain at what the Pentagon calls an unacceptably high level.

As Nick Schifrin details, a new report reveals that, within the Army, armor-brigade combat teams, which revolve around tanks, have the highest suicide rates.

NICK SCHIFRIN: Since 9/11, more than 30,000 active-duty service members or veterans of the post-9/11 wars have died by suicide.

That is more than four times the number of those who have died in combat.

Secretary of Defense Lloyd Austin has repeatedly said that even one suicide is too many and that the department must do more to prevent suicide.

A new report by The Army Times found the highest rates of suicide are among soldiers in the Army's tank community.

It was written by senior reporter Davis Winkie, who joins me now.

And I'm also joined by Craig Bryan, a former Air Force psychologist, member of a congressionally chartered study about suicide in the military, and author of the book "Rethinking Suicide: Why Prevention Fails, and How We Can Do Better."

Thanks very much, both of you.

Welcome to the "NewsHour."

Davis Winkie, let me start with you and your extraordinary report.

You found that, between 2019 and 2021, tank brigades experienced a suicide rate twice as high as the rest of the active-duty force.

Why?

DAVIS WINKIE, Senior Reporter, The Army Times: Nick, it's tragic, frankly.

New trends in suicide prevention research are linking daily hassles and sustained stress over time with higher suicide rates.

That functions by stripping away the resilience of somebody and potentially making them more vulnerable to suicidal behavior if they experience an acute stressor in their lives.

A lot of people in the Army community have known for a long time that the tank brigades are not OK, that they have been run ragged over the past decade.

But I didn't realize how deeply that had impacted service members down to the core of their beings.

There are service members who do their three- or four-year contracts and never know anything but the relentless grind that these types of units have experienced.

NICK SCHIFRIN: What you're talking about is what you call operational tempo, what the military would call operational tempo.

Talk about that a little bit more and also about what you call a lack of cohesion.

What did you find in these tank brigades that aren't necessarily in other brigades?

DAVIS WINKIE: What we found for armored brigade combat teams is that, because they have been in such high demand overseas over the past 10 years, that their op tempo, as it's shortened, got largely out of control.

They would spend nine months abroad, come home, and they would have 18 months just to prepare to do it again.

And over the course of those 18 months, they would have to spend a lot of time in the field, away from their families preparing for the next deployment, or in their motor pools fixing their vehicles for the next training exercise.

And that really compounded over time.

That combined with manning requirements that essentially say, if a unit is going to deploy to Europe, it needs to have this many of its slots filled.

What that meant functionally was that in order to have a brigade meet those requirements to go overseas, you would have to break down other armored brigades to fill in their empty slots.

And when it comes to a loss of cohesion, that's referring to the fact that tank crews would be broken up in order to achieve those administrative requirements.

And, Nick, you can't exaggerate how tight-knit and close a tank crew is.

And that loss of cohesion can't be overstated when it occurs.

NICK SCHIFRIN: Craig Bryan, let me turn to you.

What's your reaction to this?

What stands out most in these findings?

CRAIG BRYAN, Author, "Rethinking Suicide: Why Prevention Fails, and How We Can Do Better": Yes, I think one of the things that stood out to me as soon as I heard about the statistics was the focus on the tank community as a whole.

I think, when many of us think about military suicide, tankers are not necessarily what comes to the forefront of our thoughts.

We have long seen and understood suicide as something that is sort of a characteristic of the person.

And so we think of, in many ways, resiliency or suicide risk being something that a person has.

But what we understand is that over half of those who die by suicide do not have a mental health condition.

This is true within the military, as well as outside the military.

And we know that for those without a mental health condition who struggle with suicidal thoughts and die by suicide, oftentimes, it is environmental life stressors that are much more common.

The prevailing thinking right now about suicide prevention just really has not embraced that complexity.

NICK SCHIFRIN: Secretary of Defense Lloyd Austin, as I said, has discussed combating suicide as a priority.

And the department has a campaign to reduce the number of suicides, including foster a supportive environment, improve mental health care, address stigma, revise training, and promote a safety culture.

Are those working?

CRAIG BRYAN: Well, I think it's a little bit too early to tell.

Being a part of that congressionally mandated review panel last year, we offered over 100 recommendations of ways that we believe the Department of Defense could change how they approach suicide prevention.

And many of those have only started to be implemented.

And so I think it will take a little bit more time for us to see what works and what doesn't work.

But I think one of the key things, key takeaways from that committee that many of us served on was that, right now, the DOD doesn't really seem to have a centralized strategy as it relates to suicide prevention, and that a lot of the way that it thinks and approaches this issue is very reactive in nature.

NICK SCHIFRIN: Davis Winkie, is that what you have also seen, the DOD be reactive and not have a centralized strategy?

DAVIS WINKIE: What I have seen of Army suicide prevention is that, as Dr. Bryan said, it's largely focused on it as a individual problem.

That approach has -- appears to be inadequate, in that it doesn't account for systemic risk factors that cut across multiple installations, such as armor brigades and their operational tempo.

And, frankly, for them to consider that as a systemic suicide risk factor would require the Army to take a very hard look in the mirror about what it's asking its soldiers to do.

And the institution isn't always incentivized to be as self-reflective.

NICK SCHIFRIN: Eight members of the 1st Battalion of the 66th Armor Regiment, you spoke with current and former, they spoke on the record.

That is not common for those who cover the military.

Why did they do so?

And did they risk their own careers in doing so?

DAVIS WINKIE: Traditionally speaking, members of the military are not supposed to speak out on matters of policy, especially on matters of policy that could cast the service in a negative light.

And when I spoke with these soldiers and veterans, I made sure they understood the risks.

I made sure they understood the different ways they could possibly face reprisal.

And they had a number of reasons for speaking out anyways.

They were loyal to each other after having gone through so many deaths in such a short time.

They were loyal to those they'd lost.

But, most of all, they understood the message that it would send for them to put their names to their words and say, this wasn't OK.

The Army needs to hear us.

NICK SCHIFRIN: Davis Winkie, the series is called "Broken Track."

Dr. Craig Bryan, thank you very much to you both.

CRAIG BRYAN: Thank you.

DAVIS WINKIE: Thanks, Nick.