At a time when enemy threats dominate the atmosphere, the sight of space shuttle Columbia breaking apart in the sky hit Americans especially hard.
The disintegration of Columbia, which killed all seven astronauts on board, served as yet another reminder of vulnerability to a nation still recovering from the Sept. 11 terrorist attacks, and to those who remember where they were when the Challenger and all aboard it were lost 17 years ago.
"With all that is happening these days, it's a very bad feeling," said Nancy Mitchell, a hardware store clerk in Confluence, Pa. "It's just one more thing — a tragedy."
Lonnie Torsiello couldn't help but think the explosion happened at an especially bad moment for the nation.
"With everything happening in the world right now, this is one more crisis for the president to deal with," said Torsiello of North Brunswick, N.J.
The explosion made Frank Furio, an artist from New York's Dutchess County, worry more about the specter of war.
"This also makes you think twice about going to war with Iraq — it's death," Furio said as he rode a subway train in Manhattan. "That's not something the government is talking about, death, but something like this brings it closer, makes it more pertinent— when it's your loved ones, or people in your country."
Audrey Schuckhaus, of Augusta, N.J., had just arrived at the antiques shop where she works when she saw co-workers huddled around a television set. White lines were streaking across a blue screen.
"Oh my God!" she gasped.
"They went all the way up, were floating around in the atmosphere in outer space," she said. "They were almost home, so close to being safe. It's so sad."
At American Legion Post 1520 in Albany, N.Y., patrons stared at the big-screen TV from around a circular bar.
Greg Ruth, a state worker, said the shadow of terrorism, coupled with the knowledge that an astronaut from embattled Israel was aboard, made him wonder if sabotage brought down Columbia.
"For the last year and a half, I think you're going to feel that way," he said.
The experience of excitement and optimism being crushed in an instant was painful deja vu for Americans who watched the Challenger explode after takeoff on Jan. 28, 1986, as it carried teacher Christa McAuliffe.
"I saw their faces, I saw who they were and to watch this happen is just unbelievable," Traci France, 28, said as she went for a somber walk in Denver. "It really gets you, you feel it, even though you never met these people, you can think about their families and just imagine the pain. It's terrible."
Former astronaut John Glenn and his wife had just turned on their television when communication with the craft was lost as it soared across Texas.
"We were going to be watching the landing and then it got into trouble," Glenn, a former senator from Ohio, said in a telephone interview from his home at Bethesda, Md.
"It's completely shocked me," said Danny Allen, a science teacher at Cumberland County High School in Burkesville, Ky. "Nobody worries about the landing."
He and other teachers were in the middle of a space simulation at the Challenger Learning Center in Radcliff when they heard that contact had been lost with the space shuttle Columbia.
"Oh, gosh, not again," said Mohamed El Filali of Patterson, N.J., when he heard the news on his car radio while running errands. "It made me think of the Challenger, and what we went through with that. We realize that it's still dangerous. Every moment you're in the air, there's danger."
Ben Provencal, 25, of Concord, N.H., was a third-grade classmate of McAuliffe's son, Scott, and said he had feared another disaster would happen.
"I've always waited for the next thing to happen," Provencal said. "They are brave people to do that, but you just can't do this business for years and years and years without losing people."
John Baum of Lincoln, Neb., initially thought the news footage was images of the anniversary of the Challenger explosion.
"It took a while for me to realize that it was real, that it was live," he said.
Jack Fidel, a retired civil engineer in Las Vegas, had just put his waffles in the toaster when he sat down to watch television.
"The first thing I saw were the streaks of white in the sky. Everybody was dead," said Fidel, 70. "A tear came to my eye for a second. Seven people on board. What a waste of life. I had a flashback to the last explosion, then I realized what had happened."
Saturday's explosion came 17 years after the Challenger disaster. While many had become accustomed to routine launches and landings, the accident stripped away some of that security and reminded Americans of the dangers of space travel.
"You have all these hundreds of people trying to make sure these astronauts get back alive, and it's risky business," said Michael McDermott, eating at the Sisters' Cafe in Confluence, Pa., about 55 miles southeast of Pittsburgh.
Charlie Dillon went to a Denver coffee shop to reflect on the accident and read a newspaper in the warm afternoon sun.
"The reality of what these people do has often escaped me," said Dillon, 52. "But they are frontiersman, they're out there making my life better and creating endless possibilities for my children.
"These people are risking their lives, and I need to start paying closer attention to the program," he said. "I will from now on."
The Associated Press contributed to this report.