By Paul Reynolds
World Affairs Correspondent,
BBC News website
Even if he wants to, the next Pope is unlikely to exert such a global influence as did Pope John Paul II.
John Paul II's influence was felt as far afield as Latin America
John Paul II bestrode the world like a colossus.
Right from the start, when he was elected in 1978, he set out his ambitions.
Those ambitions were largely accomplished.
He re-established the conservative values of the Catholic Church.
And despite attracting criticism, for example by opposing contraception even in an Africa ravaged with Aids, he maintained his views with a humanity which was visible to all through vivid communication.
He was a political figure who had views on issues not just of eternity, but of the day.
The range of his interests demonstrates how hard it will be for anyone else to come close to matching his interventions.
He put an end to liberation theology in Latin America.
On his first visit abroad in January 1979, he told Latin American bishops in Mexico not to regard Jesus as a political activist.
"This conception of Christ as a political figure, a revolutionary, as the subversive of Nazareth, does not tally with the Church's teachings."
He helped put an end to communism in Europe.
After John Paul's visit to his native Poland in June 1979, during which the crowds chanted "We want God", the historian of Eastern Europe Timothy Garton Ash commented: "Everyone saw that Poland is not a communist country-just a communist state."
No wonder the Polish communists sent out the message: "The Pope is our enemy."
He opposed the war in Iraq: "War, like the one now in Iraq, threatens the fate of humanity."
Such a view was awkward for US President George Bush, but the American right tolerated John Paul because he stood against communism (and abortion).
The fact that the White House ignored him over Iraq shows that the temporal powers of a Pope are indeed limited, as Stalin once observed.
In the Middle East, he managed what few have achieved - he showed sympathy for and won respect from both sides of the Israeli-Palestinian conflict.
He met the late Palestinian leader Yasser Arafat and went to a Palestinian refugee camp near Bethlehem where he said: "The Palestinian people have the natural right to a homeland".
Yet he added something else in that sentence. To the right of a homeland he added: "And the right to be able to live in peace and tranquillity with the other peoples of this area."
Those other peoples of course meant principally the Israelis.
He placed a written prayer into the Western Wall in Jerusalem which called for "genuine brotherhood with the people of the Covenant".
Newspapers in Israel have mourned him as a Pope who called the Jews his "elder brothers."
Relations with Islam
He did not confront militant Islam, but pointedly sought moderation from all.
To Muslims in Damascus, he stated:
"It is my ardent hope that Muslim and Christian religious leaders and teachers will present our two great religious communities as communities in respectful dialogue, never more as communities in conflict."
Nobody else could combine such religious, political and personal power. And that leaves problems for his successor.
John Paul managed to soften the sometimes harsh doctrines of conservatism Catholicism by his personal charm.
A less sympathetic figure might trigger a reaction against some of the Church's teachings on personal morality. A less charismatic figure will have less impact in world affairs.
And yet there are possibilities.
There were gaps in the political programme of John Paul II. He spoke of his concern for the poor, yet his full weight was not felt in the current campaigns to end world poverty.
A Pope from the developing world and speaking for the developing world could be awkward for the rich.
So could a Pope who points to the deficiencies of the free market more openly than did John Paul.
Leading UK Catholic commentator William Rees-Mogg said there were two issues facing the modern world - "the material poverty of the Third World, and the spiritual poverty of the First".
In an article in the UK's Times newspaper, he wrote: "To me, these two problems suggest the advantages of a Pope drawn from the nations of suffering because they know the real conditions of life, and suffering strengthens their faith."
He described the decision to appoint Polish Cardinal Karol Wojtyla as "one of the most successful in the history of the papacy".
"I hope that the new conclave may repeat the formula which inspired the last decision. Look for the big issue and appoint the person best qualified to handle it."