Since Sept. 11, seasoned traveler Jim Stockhausen remains "much more aware that safety is a concern" every time he boards a plane. He was stranded in Germany for a week after the attacks, and it "hit home that my freedom of movement" was affected.
But as a corporate executive who flies several times a week, he's noticed an unsettling change in the people around him.
"People feel more secure. They're much more comfortable in their daily lives," he says, grasping his ticket at the Bradley International Airport outside Hartford. "But I'm not sure I'm there yet, because I fly every week."
Concern about terrorism in America has reached a new post-Sept. 11 low, despite the war in Iraq and the regular warnings from the Department of Homeland Security. Indeed, many people at Bradley International Airport last week hadn't even heard of the most recent alert about a new hijacking plot. That's just one indication that many Americans have slipped back into regular routines of going to the grocery store, the mall, and the airport without giving Osama bin Laden a second thought.
Contrast that with right after Sept. 11, when almost 50 percent of Americans listed terrorism as their top concern in a Gallop poll. Last month, less than 8 percent did.
Pollsters believe that's partly due to the time factor: It's been almost two years since Sept. 11, and there have been no more attacks on American soil.
Indeed, it's now worries about the economy and job security that have replaced terrorism as the most significant concern for almost 50 percent of Americans.
But this return to so-called "normality" has set off alarms in the community of terrorism experts, the very people who were preoccupied with Mr. bin Laden years before most Americans ever heard of him. It also prompted the administration in recent days to remind the country that it's still engaged in a war with a band of committed terrorists.
"Throughout US history, in the immediate aftermath of an attack, there's always been tremendous concern, tremendous anxiety, and then it's diminished," says Bruce Hoffman, a terrorism expert at the RAND Corp. in Washington. "The problem is that for the terrorists in this case, this is an epic struggle that can take years. They're patient and they're watching everything we do. They're simply waiting for us to lower our guard so they can strike again."
Mr. Hoffman and other terrorism experts insist they don't want to instill fear, but a pragmatic vigilance - the kind of alertness that Mr. Stockhausen exhibits, which can act as a deterrent.
Such alertness may be especially important in light of the most recent hijacking warnings. In an urgent memo sent to airlines and airport security personnel last week, the Department of Homeland Security warned that hijackers may try to commandeer planes using "common items carried by travelers, such as cameras, modified as weapons." Intelligence sources said they'd also try to convince passengers that they were orchestrating a simple hijacking, instead of trying to turn the plane itself into a weapon as they did on Sept. 11.
"The complacency that's set in compromises aviation security because we've become more reactive, rather than what's required," says Andrew Thomas, an aviation security analyst in Cleveland.
In his new book "Aviation Insecurity," Mr. Thomas faults the Transportation Security Administration for taking a defensive, law-enforcement approach to security - in effect closing the loopholes that had already been exploited - instead of taking a more proactive, deterrent approach. "Deterrence says, don't even try to come here because your likelihood of success is very low. Law enforcement says, try it and then we'll catch you," he says. "So the current aviation system is less secure than it could be."
Still, the presence of screeners in their white shirts with TSA patches on their shoulders, the baggage-screening machines that now sit next to some airline counters, and other security improvements have made many travelers feel more secure. "Obviously, they're doing something about it, and that makes me feel better," says Lily Levine, a teenager from Lebanon, Conn., who was flying to visit her grandmother in Virginia.
Pollsters are split on whether Sept. 11 was a watershed moment for the country, such as Vietnam and Watergate, which permanently shifted the country's perceptions of itself and government. Andrew Kohut, director of the Pew Research Center, believes that the terrorist attack and the threat of more has indeed caused a fundamental change in Americans.
"We know now that we are vulnerable to attacks and that we have foreign enemies," he says. "That has changed our priorities - for instance, increasing support for defense spending."
Frank Newport, editor in chief of the Gallup poll, has registered that change as well. But he hasn't found many other indications that Sept. 11 was a watershed event. "Right afterward, people talked a lot about religion and going to church, but that was a blip," he says. "We did see trust in government go up, but that is going down again."
Polls have shown that people who were directly affected by the attacks, lost family members, live in the Washington or New York areas, or were stranded for long periods of time are much more likely to have changed. Like Jim Stockhausen. He's transferring from St. Louis to the Springfield, Mass., area, which is right near Bradley International.
"I'd much rather fly out of Bradley rather than Boston or New York," he says. "It all still seems very, very real to me."