Publications
Benedict gave hundreds of spectators a two-handed wave as he stepped off a special Alitalia airliner that brought him from Rome.
Students from a local Catholic school screamed ecstatically when they saw the pope, who shook hands warmly with President George W Bush, first lady Laura Bush and their daughter Jenna on the tarmac.
Hundreds of onlookers, some from local Roman Catholic parishes, clapped and shouted as they watched the scene from nearby bleachers.
Deeply ashamed
Benedict tackled the most painful issue facing the US Catholic Church - clergy sex abuse - on his flight to America. The US church has paid out $2bn in abuse costs since 1950, most of that in just the last six years.
Seemingly in a nod to his American flock, the pope spoke in English as he answered questions submitted in advance by reporters.
"It is a great suffering for the church in the United States and for the church in general and for me personally that this could happen," Benedict said. "It is difficult for me to understand how it was possible that priests betray in this way their mission ... to these children."
"I am deeply ashamed, and we will do what is possible so this cannot happen again in the future," the pope said.
Benedict pledged that paedophiles would not be priests in the Catholic Church.
"I do not wish to talk at this moment about homosexuality, but about paedophilia, which is another thing," he said.
"We will absolutely exclude paedophiles from the sacred ministry. It is more important to have good priests than many priests. We will do everything possible to heal this wound."
Church 'complicit'
Gary Bergeron, who was molested by a priest in the 1970s in Lowell, Massachusetts, called the comments a "step I've been looking for". Bergeron said he was disappointed that Benedict did not plan to visit the Archdiocese of Boston, the scene of a case that sparked the greater scandal, but urged the pontiff to meet with victims this week.
The pope's promise failed to mollify other advocates for abuse victims, however. They said the problem is not just molester priests, but bishops and other church authorities who have let errant clergymen continue to serve even after repeated allegations.
"It's easy and tempting to continually focus on the paedophile priests themselves," said Peter Isely, a board member of the Survivors Network of those Abused by Priests. "It's harder but crucial to focus on the broader problem - complicity in the rest of the church hierarchy."
Benedict's pilgrimage is the first trip by a pontiff to the United States since the Boston case in 2002 triggered a crisis that spread throughout the United States and beyond. Hundreds of new charges - many dating back decades - have surfaced each year since. There were 691 new accusations in 2007 alone, according to an annual report from the US Conference of Catholic Bishops.
