Security Breaches Can Be Fixed. People Without Honor Can’t Be Trusted.

So now it’s clear: The Trump administration has not kept sensitive details of national security secure. Thanks to reporting by Jeffrey Goldberg of The Atlantic, we have learned that officials at the highest levels, including Vice President JD Vance, discussed military operations via chat on the cellphone app Signal, a medium vulnerable to hostile intelligence services. And they accidentally included Mr. Goldberg in the chat. Which is funny, but also, from an operational security standpoint, not great.

As the Trump administration has responded with a mixture of denials, brush-offs, lies and vitriolic attacks on Mr. Goldberg, I’ve found myself worrying less about the leak and more about the character of the people in charge of our nation’s defense. The breach is serious, but security breaches can be plugged. Men and women who have shown themselves to have no character, though, can never be trusted. Not with national security, not with anything.

Perhaps it seems old-fashioned to talk of character. We’re cynical modern Americans, after all. When idealism feels exhausted and the old order seems insufficient to meet the challenges of the modern world, candid appeals to raw interest, however amoral, can feel like a breath of fresh air. That’s part of Donald Trump’s appeal.

But there remains constant talk of character in the miliary — of integrity and accountability. This is not just for moral reasons but also for practical ones: You cannot ask men and women to go to war in a group bound by nothing stronger than self-interest. How could they trust their comrades and their leaders when their lives are on the line?

This is why a military career starts not with training in lethality but with character formation. When I joined the Marine Corps two decades ago, I entered a decidedly archaic, premodern society for which virtue was of paramount importance. At Quantico, Va. — where Mr. Vance traveled on Wednesday to speak with Marines in training — they shaved my head and put me in a uniform, because my individuality was less important than our shared purpose. Before they taught me how to fire a rifle, they taught me about honor, courage and commitment. We weren’t supposed to be hired guns; we were supposed to be the first to fight for right and freedom.

There’s a reason essentially every warrior society throughout history has had a code like this — and it’s not that every society has been enlightened. Soldiers don’t need to be saints. But to be good soldiers, to complete their missions and protect their comrades, they do need a bedrock of integrity.