Inside the gates of Arlington National Cemetery yesterday, tourists rode along in a red, white and blue bus past the headstones of the dead. With a guide in a cardboard Uncle Sam hat pointing out the notables, they rode past battalions of white memorial stones, a mesmeric sight when the sun is so hard and bright.

Far off in Section 59 Kenny Stethem stood alone before his younger brother's grave and wept. He sank to his knees, staring hard at the fresh-cut marble, then down at the soft sod beneath him.

When he could no longer bear to be so close to the stone, Kenny Stethem wandered among the evergreens and the other headstones, some of them marking the graves of marines killed in Beirut.

"My mother, she's so torn up," he said. "We're all torn up."

People have called Kenny's brother, Robert Dean Stethem, a martyr, a hero. A 23-year-old Navy diver who specialized in underwater steelwork stationed in Norfolk, Robert Stethem died brutally on June 14 at the hands of two Shiite Moslems who hijacked TWA Flight 847. "They singled him out because he was American and a soldier," his seatmate, Ruth Henderson, said. The president says "there will be no forgetting" his death.

The Stethems are a Navy family. Robert's father Richard is a retired warrant officer; his mother Patricia has held numerous administrative posts. Kenneth, 24, is also a diver and shared a house in Norfolk with his brother.

"The last time I saw my brother was mid-May," he said. "He hadn't really decided for sure whether he was going to reenlist but I was pretty sure he would. If he'd signed up for another hitch he'd be halfway to a 20-year retirement. But that's not all of it. There's nothing on the outside -- you know, in civilian life -- that's as challenging as the Navy life. You get so close to everyone. Rob did. Your lives depend on each other. Then this . . . "

The youngest Stethem son, Patrick, is 19, and he begins his Navy basic training in the autumn.

"I haven't been able to talk with Patrick much since this began," Kenny Stethem said, "but I'm sure this will just make him stronger."

Two old women in bright floral sundresses, one in yellow, one in green, walked up the grassy hill to the Stethem grave. Halfway there they stopped talking about the humidity. Slowly, they crouched to read the headstone they'd come to see:

Robert Dean Stethem, SW-2, U.S. Navy, Nov. 17, 1961 -- June 14, 1985.

"So young," the woman in green said.

The woman in yellow removed a black box camera from her shoulder bag. She aimed it at the grave with its wreaths and hump of flowers and ribbons. There was no wind, no traffic on Eisenhower Drive. It was so silent there that 20 feet away Kenny Stethem could hear the shutter click, clear as a shot. Then he watched as the women walked back down the hill and drove away.

"Such a great guy," he said, walking closer to his brother's grave. "Such a great guy . . . A great guy."

Kenny Stethem knelt once more on the moist grass. He stayed with his brother long into the afternoon.

In Waldorf, Md., where the Stethem family has lived for 19 years, Independence Day was nothing so ebullient as the parades and concerts and fireworks in the District and dozens of suburban towns. It was a quiet day of relaxing, lawn-mowing and dog walking.

In a lot outside of Carpet World and Mama Mia's Pizzeria, a few kids parked their Chargers and Trans Ams to drink a few beers and blow a rocket or two into the sky. That's about as wild as it got.

The Stethems live in a housing development just a couple of turns off Route 5.

Richard Liming used to "run around" with Kenny and Rob Stethem. They went to Thomas Stone High School together. They played football together, they lifted weights together. "We all had the same sort of ideals," Liming said. After graduation, Stethem joined the Navy. Liming went to West Point for two years before moving to Arlington, Tex., to work for an insurance company.

"I just flew in from Texas Wednesday night," he said. "I was so shocked that someone so close to me could be involved in something that international. If you would have had a group talking about fear, Rob would be the first to admit he'd be scared of something like this. But he'd be the first to act with courage. I'm frustrated. I feel real grief for his family."

A few houses down from the Stethems, Lloyd Fraser and his sons heaved pickaxes at the ground, trying to make a swimming pool. Like nearly everyone else in the neighborhood, Fraser said "it's the sort of place where you know each other but nobody bothers anybody else.

"When that boy died I tried to leave them alone. We sent a fruit basket and tried to stay away. It was tragic. I know how this sounds, but it's true -- he was a clean-cut, all-American boy. It takes the edge off the Fourth of July. Something like this brings the world closer to home. It probably brings us closer together, too."

Ed Vaughn lives around the corner from the Stethems. He works now for Sears but he spent 1965-1966 "working for the Marines in Vietnam." He stood in his driveway yesterday hitching a boat-trailer to his car.

"Believe me, I think I know what those people are feeling now," he said. "I know how it feels to lose a friend, someone you've spent time with just talking about life and all the things you do.

"I guess I ask myself, 'Why do people lose their lives for no reason? How many more times is this going to happen?' "

And Shirley Vallance, who lives four doors down from the Stethems, said, "The whole neighborhood feels sorry for what's happened. What's happened here is a tragedy. My heart goes out to them. We sent a card of perpetual remembrance, but it's such a small token.

"It's a shaky feeling we all have. It's a dangerous age we live in."

The Stethem house, like most of the other houses on Dennis Road, is squat, neat. Patricia Stethem was alone in the house yesterday. She stood behind her screen door, a thin woman made to seem still thinner by grief, and she said, no, she'd rather not talk about anything. She'd had enough with all the microphones, the cameras, the reporters, the presidential phone calls.

"I know you understand," she said. "I'm hurting. I'm hurting deep and I don't know how long it will be before I can talk about this. I'm broken up."

Then she turned away and walked downstairs to the den.

A flag was flying from a pole above the Stethems' garage, and a red, white and blue ribbon was wrapped in a bow around their mailbox. Across the street in the local ballfield a father was hitting long flies to his son.