Capt. Ryan Anthony Beaupre's relatives were watching the war on television on Thursday night when news flashed of the first American casualties, as a CH-46E Sea Knight helicopter crashed in the desert near the Iraqi border.

''You kind of get that sick feeling in your stomach,'' Captain Beaupre's older sister Alyse recalled today, ''when you know that's what your loved one flies.''

That sick feeling stuck after three marines knocked on her parents' door in this small patriotic town 65 miles south of Chicago at 3:15 this morning with the worst kind of war news.

Captain Beaupre (pronounced BOW-pray), 30, a high-school track star who quit his accounting job to join the Marines because he yearned to fly and do something more meaningful, had indeed been piloting the Sea Knight helicopter that fell in a fireball nine miles into Kuwait.

Along with Captain Beaupre, three Americans and eight British soldiers died as the helicopter crashed on its return from a mission in Iraq, probably because of mechanical failure, though officials have not ruled out hostile fire.

The other marines on board were Maj. Jay Thomas Aubin, 36, of Waterville, Me.; Cpl. Brian Matthew Kennedy, 25, of Houston; and Staff Sgt. Kendall Damon Watersbey, 29, of Baltimore. Two more marines were killed in combat today, officials said. Their names were not released.

''Of course, you think of him right away, because you know he's there, but you're like, out of all those guys, it couldn't be our Ryan,'' said Rhonda Turner, who owns the Clip & Curl here and cut Captain Beaupre's hair -- short, military style -- from the time he was in grade school.

''You'd think big stuff like that would miss a little place like this.''

This is a farm town of 1,300 people, founded in 1850, where American flags fly from every light post along the tiny downtown strip, from pickup trucks rumbling down side streets, from the window of the red-brick Beaupre home.

The Stars and Stripes are painted on the town's water tower. The marquee advertising ice for 25 cents at the liquor store is wrapped in red, white and blue bunting. Even the little Clip & Curl has a ''Support Our Troops'' bumper sticker in the window.

This afternoon, neighbors tied ribbons around trees in memory of Captain Beaupre and dropped some of those flags to half-staff.

''No one has anything against going into the Marine Corps or anything, but we were scared that something like this would happen,'' said Christopher Beaupre, 22, who was wearing a cap emblazoned with a red dragon, the sign of his brother's squadron.

''We always thought of him as a hero, regardless of this war or whatever happened.''

The first fallen heroes of this young war were remembered today in their hometowns and at their military bases, as Americans began to absorb the reality of body bags.

''He was doing the right thing,'' Tim Willet, 24, a cousin, said from the deck of the small ranch home in Winslow, Me., where Major Aubin's mother lives.

Friends and neighbors of Sergeant Watersbey, who has a 10-year-old son, sobbed in the streets of his northeast Baltimore neighborhood, according to WBAL-TV.

''I want President Bush to get a good look at this, really good look here,'' his father, Michael, said, holding up a picture of the dead marine. ''This is the only son I had, only son.''

At Camp Pendleton, Calif., where three of the four marines were based -- Major Aubin was stationed in Yuma, Ariz. -- Maj. Curtis L. Hill, a base spokesman, said the troops were in mourning.

''We've lost some of our family,'' he said, ''and when someone loses a member of their family, it's not taken lightly.''

But Lance Ewing, who retired from the Marines 17 years ago and still lives near the base, on a boat in Oceanside Harbor, said he was surprised there had not been more casualties.

''These boys know what they're getting into,'' he said. ''Hell, we all do. It's our job as marines. Tell us what you want to do and then get the hell out of the way.''

Here in St. Anne, a memorial Mass for Captain Beaupre was held this morning at the Roman Catholic church, and 15 miles away at his alma mater, Bishop McNamara High School in Kankakee, a dozen students clasped hands and said the Lord's Prayer after lowering the flag halfway.

Alyse Beaupre, 31, said her brother got a job at an insurance company after graduating from Illinois Wesleyan University in 1995, but soon quit to join the Marines because ''he thought that he could do more as a person.''

He got his wings four years later, and shipped out to the Persian Gulf in February.

''He just wanted to call and tell me that he would be leaving to go overseas, and I asked him all the typical questions, you know, 'Are you scared?' '' Ms. Beaupre recalled of their last conversation. ''I wanted to know if he was O.K. with what he was going over there for. He was. He said that this was something that needed to be done.''

The family had received three letters since Captain Beaupre deployed, but no phone calls. ''He told us that it was a long wait in line to use the phone for a short amount of time,'' Ms. Beaupre said today, ''and that that right should be reserved for those with wives and children at home.''

A handsome redhead with a broad smile, Ryan Beaupre finished the Chicago marathon last fall. In high school, he captained the track and cross country teams, and ran the lead-off leg to win the 1991 state championship of the 1,600-meter relay.

At Wesleyan on a partial track scholarship, he joined the Sigma Pi fraternity, where his adviser, Jack Fields, said ''he was always the one who got the guys to pay their dues.''

''Ryan was the one you depend on to make sure things happen, to carry out a plan and see to it that all of the details are attended to,'' recalled Mr. Fields, the university registrar. ''It's hard to say no to someone who is standing up and doing the right thing all the time.''

Sharon Jackson, director of development at Bishop McNamara, said today that she could ''still see Ryan walking down the hall with his grin and red hair, high-fiving everyone.

''I don't know that Ryan ever had a bad day,'' she added.

His high school track coach, Ken Klipp, said Captain Beaupre had been an ideal role model, a kid-next-door type whose straight A's landed him in the National Honor Society.

''First one into the action, which is sort of what he's like,'' Mr. Klipp said, speaking both of his relay position and his role in this war.

This morning, as news of the crash reverberated through the school, Mr. Klipp noticed a change in his students.

''The circumstances make it personal,'' he explained. '' 'Hey, he graduated here, it could be you, it could be me.' It's not a headline, it's not a story anymore. It makes it real.''

In the hallway this afternoon, a dozen students crowded around the bulletin board where, for weeks, they have posted articles and scrawled slogans debating the war: ''Regime change begins at home.'' ''Pray for the return of our soldiers.'' ''War is also terrorism.''

And now, someone has added: ''Ryan Beaupre gave his life for us, what's wrong with that?''