President George W. Bush, members of Congress and ordinary Americans paid tribute to Rosa Parks under the soaring dome of the Capitol Rotunda on Sunday, honoring the woman whose defiant act on a city bus challenged race segregation in the South and inspired the US civil rights movement. Parks, a former seamstress, became the first woman to lie in honor in the Rotunda, sharing an honor bestowed upon Abraham Lincoln, John F. Kennedy and the nation's highest leaders. Bush and congressional leaders paused to lay wreaths by her casket, while members of a university choir greeted her with "The Battle Hymn of the Republic." Rep. John Conyers, a Michigan Democrat, for whom Parks worked in his Detroit congressional office, said the ceremony and public viewing showed "the legacy of Rosa Parks is more than just a success for the civil rights movement or for African-Americans. It means it's a national honor." Outside the Capitol, thousands of people awaited the chance to pay their respects, some arriving before noon to be able to file past her casket. Some carried signs that read, "Thank you, Rosa Parks." Parks, who died last Monday, was arrested in 1955 for refusing to give up her bus seat to a white man. Among those who supported her was Dr. Martin Luther King Jr., who led the 381-day boycott of the city's bus system that helped initiate the modern civil rights movement. Her casket was carried from the hearse by a military honor guard while Rep. Carolyn Kilpatrick, a Michigan Democrat, stood with family members and friends outside the steps leading up to the Capitol and prayed. The motorcade included a vintage bus draped in black bunting. Senate chaplain Barry Black, bowing his head in prayer, said Parks' courage "ignited a movement that aroused our national conscience" and served as an example of the "power of fateful, small acts." Bush, who was not speaking during the brief ceremony, issued a proclamation Sunday ordering the US flag to be flown at half-staff over all public buildings on Wednesday, the day of Parks' funeral and burial in Detroit. Outside the Capitol, thousands of people came to pay their last respects. Fred Allen, 59, who grew up in segregated Halls, Tennessee, brought his 20-year-old son to help him understand the civil rights era. "He has no idea what it was like to grow up in the South, where you had to hold your head down," Allen said. Robert Cunningham, 65, caught a flight from Atlanta with his wife, daughter and four grandchildren so they could pay their last respects. When they learned Friday night that Parks' body would lie in honor in the Capitol, Cunningham's wife said, "We have to go." "She started the movement," Cunningham said of Parks, staring at the West facade of the Capitol. "She was the mother of the civil rights movement by simply saying, 'I'm tired of giving up my seat.'" "She was a citizen in the best sense of the word," said Sen. Tom Harkin, a Democrat from Iowa, one of several lawmakers who paid homage to Parks. "She caused things to happen in our society that made us a better, more caring, more just society."