President John F. Kennedy talks with Pope Paul VI at the Vatican on July 3, 1963. The meeting was historic: the first Roman Catholic president of the United States was seeing the Roman Catholic pontiff only days after his papal coronation. (Associated Press Files)

WASHINGTON — The leader of the world's one billion Roman Catholics has been to the White House only once in history — but that will change this week.

Pope Benedict XVI will be met by the president himself when he arrives in the U.S. on Tuesday. George W. Bush is pulling out all the stops, driving out to a suburban military base to meet the pope's plane, bringing a giant audience to the South Lawn and hosting a fancy East Room dinner.

These are all firsts.

Bush has never before given a visiting leader the honour of picking him up at the airport. In fact, no president has done so at Andrews Air Force Base, the typical landing spot for modern leaders.

A crowd of up to 12,000 is due at the White House Wednesday morning for the Pope's official, pomp-filled arrival ceremony.

The evening festivities will mark the first time the Bushes have put on a high-profile meal in honour of someone who isn't even a guest. Benedict's prayer service that evening with U.S. bishops at a famed Washington basilica preclude him from coming to the dinner. Catholic leaders will be there instead.

The president explained the special treatment — particularly the airport greeting.

"One, he speaks for millions. Two, he doesn't come as a politician; he comes as a man of faith," Bush told the EWTN Global Catholic Network in an interview. He added that he wanted to honour Benedict's conviction that "there's right and wrong in life, that moral relativism has a danger of undermining the capacity to have more hopeful and free societies."

64 million reasons to meet

The Bush-Benedict get-together will be the 25th meeting between a pope and a sitting U.S. president. Jimmy Carter was the only other president to host a pope at the White House, receiving a 1979 visit from Pope John Paul II.

The first papal audience with a U.S. president did not come until shortly after the end of the First World War, when Woodrow Wilson was received at the Vatican by Pope Benedict XV in 1919. The next wasn't for 40 more years, when President Dwight Eisenhower saw Pope John XXIII in Rome.

Since then, such audiences have become a must-do. Every president has met with the pope at least once, often more. This week makes Bush the record-holder, with a total of five meetings with two popes.

There are more than 64 million reasons for this. Catholics number nearly one-quarter of the U.S. population, making them a desirable constituency for politicians to court.

"The pope represents not just the Catholic Church but the possibility of moral argument in world affairs, and it is very important for American presidents to rub up against that from time to time," said George Weigel, a Catholic theologian and biographer of Pope John Paul II.

The Vatican — seat of a government as well as a religious headquarters — has an interest, too.

"It wants to be a player in world affairs, and everyone understands that to do that you have to be in conversation with the United States," said John Allen, the Vatican correspondent for the independent National Catholic Reporter.

'A lot of things to talk about'

On social issues such as abortion, gay marriage and stem cell research, Bush and Benedict have plenty of common ground.

But they disagree over the war in Iraq, just as Bush did with Benedict's predecessor, John Paul.

When Benedict was a cardinal before the 2003 invasion, the now-pontiff categorically dismissed the idea that a preventive strike against Iraq could be justified under Catholic doctrine. In his Easter message last year, Benedict said "nothing positive comes from Iraq."

In fact, the death penalty is another area of long-held disagreement, with Bush a strong supporter. Benedict also speaks forcefully against punitive immigration laws and the U.S. trade embargo against Cuba and in favour of environmental protection and social welfare — all in ways that often run counter to the policies of the Bush administration.

But differences between popes and presidents are nothing new.

John Paul and former president Bill Clinton clashed — with strikingly sharp Vatican statements — on abortion.

Also, the church's opposition to almost any war except those based on self-defense has been a persistent theme in U.S. relations.

Pope Paul VI wanted to help mediate an end to the Vietnam War. John Paul also urged then president Ronald Reagan against the arms race and spoke out vigorously against the 1991 Persian Gulf War under the current president's father. All these urgings, like the current anti-Iraq argument, were to no avail.

"Modern popes have seen themselves as voices of conscience and peacemakers," Allen said. "U.S. administrations haven't always been excited for them to play that role."

Weighty discussions aside, the talks with Bush are not likely to be the most-remembered or most influential part of the pontiff's six-day, two-city U.S. tour, Weigel said. That is expected to come when Benedict addresses the United Nations on Friday.

"I think it's nice they're going to meet. They have a lot of things to talk about," he said. "But the notion that the world operates by the big guys getting together and cutting a deal is wrong."

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