In a rare gesture, President Bush traveled from the White House with first lady Laura Bush to greet Pope Benedict XVI after his plane landed Tuesday afternoon at Andrews Air Force Base outside Washington, D.C.
It's the first time that Bush has left the White House to greet a foreign dignitary, and the first official papal visit to the United States since the establishment of full diplomatic relations between the United States and the Vatican 24 years ago.
"Obviously, it shows the deep respect that the president has for the pope and also the recognition that there's a lot of Catholic voters out there," said Father Thomas Reese, a Jesuit and senior fellow at Georgetown University's Woodstock Theological Center.
Walking on a red carpet, the president warmly greeted the pope shaking his hand after he emerged from his plane, nicknamed Shepherd One.
As he was getting into the back of his limousine, the crowd at Andrews Air Force Base in Maryland sang a few bars of "Happy Birthday" to the pope, who turns 81 on Wednesday.
ABC News contributor Cokie Roberts was invited to ride with the president, the first lady, and first daughter Jenna Bush, for his unprecedented trip from the White House to greet the pope at a military base in Maryland.
"The president said the pope is a worldwide spiritual leader and that millions of American citizens are excited about having him in this country and that he, the president, wanted to go to Andrews Air Force Base as a sign of respect," said Roberts, whose mother, Rep. Lindy Boggs, D-La., was the U.S. ambassador to the Vatican from 1997 to 2001.
"He said the pope is major figure in the world and more people listen to him than anyone else in the world," Roberts said.
This is Benedict's first visit to the United States, and the first chance for many Americans to get an up-close view of the man who succeeded the charismatic and popular late Pope John Paul II. Benedict has won praise from religious scholars for his emphasis on the marriage between faith and reason.
Benedict has denounced terrorism as a separation of religion and reason.
During his six-day visit to the United States, the pope will address the United Nations on the 60th anniversary of the UN declaration on human rights.
Both he and his predecessor publicly denounced the president's decision to wage war unilaterally against Iraq. The pope is expected to call for a diplomatic and political solution rather than a military solution to the violence in Iraq that has left Christian minorities there vulnerable.
"I think the pope will be pretty diplomatic," Reese said. "He's not going to wag his finger at the president, even though he has disagreed with him. ... He's not going to stand on the White House lawn and say, 'Pull the troops out immediately.'"
Bush will host Benedict Wednesday for a private 45-minute meeting in the Oval Office after an elaborate official arrival ceremony with more than 9,000 invited guests expected on the South Lawn, more than were present for the arrival ceremony for Queen Elizabeth II last May.