My brother died to buy a bit of time.

There he was, 30 days into his tour, hunkered down on a hot May evening. Reconnaissance reported enemy troops dug in just steps beyond the ridge line, patiently waiting for dark to overrun and kill everyone in my brother's company.

The sun was setting. The order came to charge. My brother flew over the ridge, an anonymous new guy to the men who covered his attack.

Amped, no doubt, on adrenaline, he must have struggled to recall his basic training. M-16 on automatic, he descended into the crossfire of two rattling machine guns. Bullets shredded his body, no part spared.

That charge and two others before dawn did what they were meant to do. They showed force. They scattered the enemy into the hills. They bought some time.

The price of that night in Vietnam? Nine dead Marines, one of them my brother.

The war in Iraq, with its horrifying body counts and obituaries, has set me to contemplating the bizarre calculus of military life and death.

My brother was no raging patriot, and he didn't pay much attention to the public policy that trapped us in Southeast Asia. He was a tough kid doing his best to escape a violent, tyrannical father and the family economics that kept us teetering on the edge of poverty. He had no appetite for college, and he joined the Marines in frustration when the Navy turned him down for a shot at becoming a vehicle mechanic. His biggest dream was to use what he could save from his Marine Corps pay to buy a Ford Shelby Cobra when he returned from Vietnam.

Still, boot camp infused him with the gung-ho desire to prove himself a worthy warrior. He came home one evening after advanced infantry training with his inhibitions loosened by a pint of Early Times whiskey. Dying was on his mind. "Tell Mom and Dad that if I get killed, they'll never phone or send a telegram," he said. "Someone will always come to the door."

I tried deflecting this uncomfortable line of conversation, but he insisted. "Is it true they're having money problems again?" I told him yes. He said that if he was killed the family would get a $10,000 insurance payment and funeral expenses.

Was that gratifying thought on his mind as his life drained down the ridge? Probably not. My guess is that he was angry about getting himself shot.

Today, I'm struck by the extent to which I cannot bring myself to believe that Jim's rationale for becoming a Marine factored in the grand ideals of dying for America's freedom, of liberating the oppressed or the other noble causes touted then and now.

Rather, I think he naively accepted the warrior worship he'd been fed by superiors about all of those so-called heroes who preceded his trip home in a coffin.

I miss Jim unremittingly, and wish I could ascribe a higher purpose to his death.

But I know now, having shared many long emotional conversations with Marines who were there that night, having watched another three decades of history unfold, that he died for this cause only: To buy time.

Jim and those eight other young men bought another night for their fellow Marines. That was honorable.

But their deaths, combined with all those thousands of others, also bought more months for the American civilian and military leaders to harass a determined insurgent enemy; for then-Defense Secretary Robert McNamara to lose faith that the war was winnable, let alone justified; for Henry Kissinger to muddle through the Paris talks toward Richard Nixon's "peace with honor."

And now, each time I read about another soldier blown apart by a roadside bomb, I recoil from this sickening paradox: That it took all those sons' and brothers' deaths to buy enough time for Americans to finally weary of politicians' pep talks and end a pointless war.

Paul Vandeventer runs a community development organization in Los Angeles. He wrote this commentary for the Los Angeles Times.