"John!" called my brother from the living room. "Are you coming out or not?"

He and my sister-in-law were eager to start the movie we had rented, but I, lurking in my parents' darkened study, waved them off. While they and the rest of the family were distracted, I had private business to attend to on the home computer.

It was December 2001, and I was a New Yorker.

Of the innumerable moments of surreality accompanying Sept. 11, 2001's fracturing of our daily lives — fighter jets circling the city, a pillar of ash rising to the stratosphere, New Yorkers engaging in spontaneous conversation — here was a doozy: finding myself at my parents' home in California for Christmas, nosing furtively about the Internet for information on getting into the U.S. Army's Officer Candidate School at Fort Benning, Ga.

It seemed on the one hand an entirely reasonable thing to be doing, and on the other an outrageous one. Reasonable because the military would probably need the services of motivated citizens in the near future, and I was a motivated citizen. Outrageous because I, a lawyer with no military experience, knew virtually no one from my own background — comfortable childhood, good education, white-collar career — who had ever been in the service.

In law school, I did sign up for "informational interviews" — they didn't dare hope for actual employment interviews at Berkeley — with some of the services' JAG Corps representatives and was later informed by a fellow student that I was the only bona fide interviewee. The other students on the roster intended to read statements of protest regarding the Defense Department's "don't ask, don't tell" policy.

Such experiences over a young lifetime coalesce into prejudice: People like us — the privileged, frankly — don't join the military. The armed forces are for another sort of American. Right?

It took me most of a year to get serious and walk a block from my apartment to the recruiting center at 22nd Street and 6th Avenue in Manhattan, and another year to slog my way through the Army's truly dysfunctional officer recruiting process.

During this period I harangued myself continually: How does one train physically for this? Will my 29-year-old body hold up? Am I mentally resilient enough to handle the "suck factor" of an intense program such as OCS? Am I personally forceful enough to be a leader in the military?

In short, can I hack it?

Today I am a first lieutenant with a platoon of 50 men. As of October, I have been in the service for three years, and I have spent the past year in Iraq. I believe I've been as successful as any of the other junior officers in my unit.

Which ought to surprise me, given my prior prejudices about what sort of person is fit for the military. I was never the captain of the team. Then one day in 2005, I found myself lugging a 60-pound rucksack and a rifle across Fort Benning and rappelling and picking my way through a dark forest with night-vision goggles.

After that, I was on to my first unit to flounder about and find my way as a new officer. Then last year, I found myself amid the maddening impenetrable politics of Anbar province.

Along this road I discovered something about myself, and about the military.

About myself, I discovered that there were within me — within everyone — latent abilities, tendencies, temperaments that only an environment such as this will bring out. And yes, I'm speaking to you bookish types now. However well you may think you know your own pacific constitution, be assured that there is someone more physical and forceful within you — someone you will meet, given the right circumstances.

About the Army, I learned that it can be a hard — and hardening — environment, but by and large the people in it are just people. They are not uniquely tough by nature, though they become so through training and preparation and habit. And their toughness is leavened with a deep sense of common humanity — a basic unquestioning rarely found in the "softer" cosmopolitan world of ambition and sophistication from which I hail.

The privileged of prior generations were more likely to consider military service a natural expression of their own privileged relationship to the state — the least, you might say, that they could do in return for the opportunities the nation had granted them. Consider a young John F. Kennedy working connections to obtain a commission that his health would have denied him otherwise.

All else being equal, staffing the armed services with citizens from the broadest range of backgrounds is still the best course. Further, we are in a time, and a conflict, in which the unique demands placed upon the military make the need for innovative leadership acute.

Am I simply recruiting among the elite, then? No. But I would regret knowing that some who might have served did not do so because of the same lazy prejudice that I once held — the barely conscious assumption that some Americans are at once too good, and not good enough, for the military.

John Renehan is assigned to the 1st Brigade Combat Team, 3rd Infantry Division, and is currently stationed at Camp Ramadi, Iraq.