Americans are marking the fifth anniversary of the September 11 terrorist attacks by observing moments of silence and reading the names of the victims. The attacks killed almost 3,000 people. President and Mrs. Bush began the day attending observances in New York City, where the first two of the four hijacked planes struck the World Trade Center, causing the two towers to collapse.

Mourners toss flowers into a reflecting pool during a ceremony Monday, September 11, 2006 at the World Trade Center in New York

Across America, sorrow and anger still resonate -- five years after the worst terrorist attack on U.S. soil.

At the former site of the World Trade Center, bagpipes played as firefighters remembered their fallen colleagues and carried the American flag that flew there that day. Three hundred forty three firefighters and paramedics died while trying to rescue people in the World Trade Center complex.

Throughout the morning, family members read aloud the names of the more than 2700 people who perished at the spot that has become known as "Ground Zero."

They also shared personal remembrances.

James Smith is the widower of New York City police officer, Moira Smith. She died in the collapse of the South Tower. "She'd still be protecting the people of the city she loved, defending the nation she loved, keeping it from harm," he told the crowd. "And she would be raising the child she loved more than anything on earth. But most importantly, Moira would be about the business of living. She would be making us smile when we wanted to frown and laugh when we wanted to cry."

Former New York City Mayor Rudolph Giuliani earned nationwide praise for his leadership during and after the attacks. He honored the victims' legacy by quoting Ralph Waldo Emerson.

"To leave the world a better place, whether by a healthy child, a garden patch, or a redeemed social condition. To know that even one life has breathed easier, because you lived -- this is to have succeeded."

At the Pentagon, where 184 people died, Vice President Dick Cheney said the sting of the September 11th attacks will linger forever among Americans.

"Nine-Eleven is a day of national unity. The memories stay with all of us because the attack was directed at all of us. We were meant to take it personally, and we still do take it personally."

President and Mrs. Bush began the day by observing a moment of silence at a New York City firehouse whose firefighters were among the first to respond to the scene. The battalion's chief died at Ground Zero.

Later in Shanksville, Pennsylvania, President Bush laid a wreath at a memorial honoring the 40 passengers and crewmembers of United Flight 93 -- the one hijacked plane that did NOT reach its target. Voice recordings indicate some passengers tried to overpower the hijackers, foiling their plans to crash the plane into a fourth target.