The crash of American Airlines Flight 587 in New York City yesterday was a large tragedy in its own right. But coming two months and a day after the World Trade Center attacks - on another calm, clear morning - it instantly grabbed the attention of the world.
Even if the cause turns out to be mechanical failure (and there is no other indication at this writing), this accident adds a new level of difficulty to the test of resilience that Americans have faced since Sept. 11.
It deals a blow to the airlines facing their most crushing financial squeeze in decades, to New Yorkers rebuilding their city and its economy, and to Americans strugging to overcome their newfound sense of vulnerability.
"American public opinion is on something like a knife edge," says political analyst Kevin Phillips. "Americans would like to think that Sept. 11 was the second Pearl Harbor, and they would come back bigger and stronger than ever. But parts of them doubt that."
The American Airlines jetliner went down just moments after taking off from Kennedy Airport Monday. It was en route to the Dominican Republic with 255 people on board. It crashed in a residential section of Queens, setting homes and buildings ablaze.
Early reports suggested that an explosion occurred aboard the plane. But White House officials, in their first briefing after the crash, downplayed that idea. One FBI source said there was no early evidence of any terrorist involvement.
White House spokesman Ari Fleischer noted that there were no unusual communications between the plane and the control tower. The National Transportation Safety Board is the lead agency investigating the crash - another sign that the government is treating the crash as an accident.
Still, since Sept. 11, Americans, almost instinctively, have come to suspect the worst behind every disaster - whether it's a plane crash or powder on a letter.
"The immediate response here was that something foul had taken place," says New York-based pollster John Zogby. "It brought out two memories - a plane crashing and New York City. The spontaneous reaction was, 'Oh no, not again.' "
Unfortunate, too, is that the crash hit at a time when, as Mr. Zogby puts it, the "fear index" had been declining dramatically in the United States since Sept. 11 - particularly about flying.
The crash marks a particular blow to New York City, which is still trying to return to some semblance of normalcy. Robert Kraus, a professor of psychology at Columbia University, says just the sound of emergency vehicles makes him jumpy these days.
"The knowledge of what's happened is never very far beneath the surface for New Yorkers - and so it's triggered by stimuli that's associated with it. For me, it's the sound of emergency vehicle sirens."
In fact, on Monday morning hundreds of emergency vehicles rushed out to the Rockaway section of Queens, where the American Airlines flight went down. Early footage showed an engine housing lying outside of a gasoline station. Fire crews worked to douse burning houses.
Almost immediately after the crash, New York went into its now-familiar defensive posture - uncertain whether this was an airline crash or a terror attack. Bridges and tunnels were shut down for several hours. Fighter jets roared overhead, and all three major metropolitan airports were shut down. Federal authorities, though, kept the rest of the nation's air-travel hubs open.
Some streets in New York were closed except for emergency vehicles. Mayor Rudolph Giuliani, for his part, was forced to play the role of stern-but-soothing leader once again. He cautioned against jumping to conclusions about the reason for the crash and said no city was better prepared than New York.
The crash immediately reverberated from Queens to midtown Manhattan, where heads of state were supposed to gather at the United Nations. Instead, the UN went into a partial lockdown as well. President Bush, in the city for UN meetings, canceled several planned events.
Even though initial reports seem to indicate the flight was normal up until the crash, for some New Yorkers the tragedy raised other worries. That's the case with Steve MacDowell, executive assistant for a large charitable foundation.
"I think we've all become slightly more conspiratorial, even in the face of something that may clearly be an accident," says the Bronx resident.
Others note the proclivity of Americans to jump to conclusions now, as well. "We're now suspicious when anything like this happens," says Alan Wolfe, director of the Boisi Center for Religion and American Public Life at Boston College. "Before Sept. 11, the benefit of the doubt was, 'It was an accident.' Now that's no longer true."
Contributor Harry Bruinius in New York and staff writers Abraham McLaughlin and Gail Russell Chaddock in Washington and Liz Marlantes in Boston contributed to this report.