The Big Question: Will the Pope's trip to the United States resolve the crisis in Catholicism there?

Why are we asking this now?

Because today Benedict XVI makes his first visit to Washington. Unlike his much-travelled predecessor, John Paul II, who visited the US seven times, the new Pope in three years in office has made just seven trips outside Italy, only two of them outside Europe. And instead of a barnstorming continent-wide tour, Benedict will visit just two cities, Washington and New York.

How grave is the crisis?

The sex abuse scandal which erupted in 2002 has taken a significant toll on the reputation and finances of the Catholic Church. It revealed more than 5,000 victims, and has made five dioceses bankrupt. Just last year, the Archdiocese of Los Angeles agreed to pay $660m to 500 victims of abuse dating back as far as the 1940s – the largest of several compensation settlements which have cost the church $2bn to date. And it's is not over. Just last week the family of two young boys filed a lawsuit accusing a Massachusetts priest of molestation as recently as 2005.

The accusations have been made against a small minority of the nation's 45,000 priests, but Pope Benedict is taking a much tougher line than his predecessor. Before his election as pontiff, the then Cardinal Joseph Ratzinger described such priests as "filth", and one of his first acts in office was to discipline the founder of one of the Vatican's favoured conservative orders, the Legionaries of Christ, who had been accused of sexually abusing boys decades ago.

Will he tackle the issue of paedophile priests?

Yes. He will raise it when he meets with the 350 US bishops in Washington tomorrow and at two separate occasions in New York – at a gathering of nuns and priests and a separate meeting of seminary students. Breaking with tradition, he is allowing the media access to his meetings with the bishops.

What about the decline in church attendance?

That is certainly an issue. According to a recent poll a third of US citizens were raised as Catholics, but today only a quarter describe themselves as Catholic. The number of priests ordained in 2007 fell to 456 – half the number in 1965. Hundreds of parishes are being closed and consolidated, because of the shortage of priests, falling funds to maintain the buildings or demographic changes.

Having said that, this is far from a decline on the scale experienced in Europe. The US Catholic Church is still four times the size of the next largest group, the Southern Baptist Convention, even though the latter make more noise in political and media circles. The US still has the third largest Catholic population in the world after Brazil and Mexico. And one in three of its members go to Mass at least once a week.

So what is keeping the church alive?

The old strongholds of the church were the ethnic inner-city parishes of Italian, Irish, Polish Catholics. Many of these are closing, but new ones are opening in the suburbs to which these groups have migrated with their increased affluence.

Some of thee old churches are closing, but others are being taken over by a new wave of immigrants from Latin America, the Philippines and Africa. In some parishes the new mix has been joyous, in others uneasy. But a new multiculturalism is characterising US Catholicism. And with Hispanic groups now constituting 29 per cent of all US Catholics, the church is increasingly becoming bilingual.

What will the Pope say about all this?

Well, he won't be able to go on about secularisation as much as he does in Europe, though his attacks on relativism and materialism will probably get an airing. He may have something to say about what the Vatican condemns as the "pick'n'mix" nature of American Catholicism.

Accustomed to the business of democracy, US Catholics have a determinedly independent streak which puts them at odds with Rome on a number of issues: 60 per cent support the death penalty; 55 per cent back stem-cell research; 51 per cent think abortion should be legal in all or most cases; and 42 per cent favour gay marriage – a higher percentage, indeed, than the rest of the country (though the new Catholic immigrants, especially Hispanics, tend to be more in tune with this conservative Pope).

There is something else. The sex abuse scandal has made many Catholics more confrontational. Lay Catholics across the country are demanding more control and more financial accountability from their bishops. They are occupying churches to fight closure plans. Last month a group of 45 priests contacted Rome to demand their bishop step down, accusing him of misappropriating more than $17,000 and using it to buy liturgical garments and furniture.

It is, though, important not to overstate this new independence. A Georgetown University survey this week showed that 70 per cent are satisfied with the leadership of their bishops compared with just 58 per cent four years ago, when the priestly sex scandal was at its height.

Is the visit an attempt to influence the election?

Probably not. The Catholic hierarchy got embroiled in the 2004 election, when a handful of conservative bishops threatened to withhold Communion from Senator John Kerry because of his pro-abortion stance. But this time candidates Clinton, Obama and McCain all support embryonic stem-cell research and have voted in favour of same-sex partnerships.

It is possible that if the Pope focuses on abortion that will be seen as favouring the Republican side, and if he speaks for world peace and against capital punishment and punitive immigration policies, that may be seen as pro-Democrat. But neither will be his intention.

Which way is the Pope likely to lean?

On Friday he will make a major speech to the United Nations General Assembly in New York. His themes will be globalisation, persistent poverty in the developing world, the environment and global warming, and he will applaud the UN decision to ban the death penalty worldwide.

And while he will have plenty in common with President Bush on abortion, gay marriage and stem-cell research, he intends to make his feelings clear on the disastrous war in Iraq. Though he will attend a reception in the White House, he has made it clear that he will skip the state dinner in his honour as a protest over the Iraq war. It is not the kind of snub presidents of the United States are much used to.

Can President Bush count on the support of the Pope?

Yes...

*The Pope will endorse the President's anti-abortion stance and his decision to withdraw public funds from stem-cell research

*Mr Bush will applaud the Pope's decision to pray for the conversion of Islamist terrorists at Ground Zero

*The Pope's presence could consolidate the swing at the last election of Catholic voters from the Democrat to Republican party

No...

*The Pope will back the United Nations against the Bush administration on a number of issues

*Benedict XVI will dismiss Mr Bush's defence of capital punishment in the United States

*The Pope will be unsparing in his criticism of the US-led invasion of Iraq