CBS News medical correspondent Elizabeth Kaledin takes a look at the facts versus the fears.
For the first time in 100 years, American streets are the frontlines, and civilians are facing an enemy both visible and invisible.
The heightened mood of national pride has recently been countered with a growing sense of public dread. As each day brings a new anthrax scare and threats of more to come, fear is emerging as America's new enemy.
According to psychologists, fear is a complex phenomenon: part emotional, part physical, and often an important survival instinct:
Karen Sitterle, a clinical psychologist at the University of Texas, says fear is our body's way of sounding "an alarm that we need to be alert or on guard."
But fear can also be destructive and irrational. In the case of recent events, it has surfaced in the form of people who stockpile drugs they don't need, buy gas masks that won't help them, and even avoid leaving the house.
According to Sitterle, this is the very response that the terrorists wanted to achieve. "They create a sense that anyone--anytime, anyplace--can become a victim."
Creating fear in an unseen, lurking enemy has been a trade tool of Hollywood for years. In Jaws, Steven Spielberg's classic scary movie, the shark did not appear on screen for the whole first hour of the film.
Spielberg once explained the reasoning behind his ploy: "I don't know of anything more terrifying than off-camera violence," he said in an interview.
In the face of the real-life unknown, experts say the best way to counter fear is to arm yourself with knowledge: Get informed, stay connected, and put your feelings in perspective.
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