All that changed at 8:45 a.m., when the first of two hijacked commercial airliners slammed into the World Trade Center, killing some 5,000 people and forever altering the city, the nation and the world.
On Thursday, as U.S. and British jets pound military and terrorist targets in Afghanistan, and as the seemingly endless procession of funerals for New York's fallen and the slow cleanup of the downtown disaster site continue, America marked the one-month anniversary of the attacks.
President Bush, former President Clinton and other dignitaries joined victims' families at a memorial ceremony at the Pentagon, where 189 people died on Sept. 11 when hijackers slammed a jet into the military headquarters.
The hijackers "were instruments of evil who died in vain," said the president. "The terrorists have no true home in any country or culture or faith. They dwell in dark corners of earth and there we will find them," he vowed.
At lower Manhattan's Ground Zero, work stopped Thursday morning when Mayor Rudolph Giuliani joined weary cleanup crews at the site for prayers and a moment of silence.
"Don't look at the terrorism over there, look at the heroism over here," said Rabbi Joseph Potasnik, a Fire Department chaplain, as workers took off their helmets and joined arm in arm.
Colleges and universities are marking the day with services at their chapels, and symposiums on issues raised by the attacks.
Houses of worship are holding special services, including extra hours for confession at Roman Catholic churches. Thousands of restaurants are donating a share of the day's profits to aid families of the victims. Many communities are observing moments of silence or conduct candlelight vigils.
At the urging of the Alliance of North American Pipe Band Associations, bagpipers across the United States, and as far away as New Zealand, are playing in memory of the victims.
Bert Heyvaert, a piper from Belgium, said he would play at the American memorial in Ypres, site of a devastating battle in World War I.
"My respects to the (New York) rescue workers and all those who have not given up hope in their wounded city," he wrote in a message to the pipers' association. "I'll be proud to honor all of you."
One month later, Americans are still adjusting to the events of that grim September morning which jolted the country out of its sense of invulnerability into a new world of security checks, bio-terrorist threats, war and fear.
The attacks affecte the country in tangible and intangible ways, touching our hearts and minds, our homes and our families, as well as our pocketbooks.
We learned the names of a new set of enemies from a distant part of the world: Osama bin Laden, al-Qaida, Taliban. And we learned the names of new heroes from the New York City police and fire departments.
The nation prepared for a long and costly war on terrorism abroad, and readied itself for the threat of fresh attacks at home.
Americans voiced overwhelming support for military action, with 87 percent approving of U.S. air strikes on Afghanistan, and just 6 percent disapproving according to a CBS News poll. The president's approval ratings also skyrocketed.
Stock markets tumbled in the wake of the attacks, and the president proposed a stimulus package of at least $60 billion to revive the sinking economy. Congress approved a $15 billion emergency bailout for the ailing U.S. airline industry, which lost 100,000 jobs after Sept. 11 as the flying public stayed home.
Television networks offered five days of nonstop, commercial-free coverage of the crisis, and Americans donated billions of dollars to help with relief efforts and to provide support for victims' families.
Newfound patriotism was evident in public displays of American flags, while hate crimes and incidents of violence were reported against members of Muslim, Arab and Sikh communities.
Mostly, one month after the deadliest terrorist attacks ever, the nation grieves and waits, uncertain and fearful, but determined and united.
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