What has changed since the last papal visit in 1982? When I read the reports from 27 years ago, one answer leaped right out: it is the collapse of Anglican self-confidence, which has gone hand in hand with the collapse of English or British pretensions, too. In 1982, Enoch Powell could write to the Times pointing out that if the pope set foot in this country it would prove that the Queen could not be "on earth the supreme governor of the Church of England". In 2009 no one of importance supposes that she might be.

Pope John Paul II arrived in the middle of the Falklands war, which seemed at the time to many people like a return to past glories but now seems to be almost certainly the last war that Britain will ever fight in defence of its own former empire. Nowadays, of course, we're merely barbarian auxiliaries for the emperor in Washington.

But it wasn't just the British or English self-esteem which has plummeted since then. It is also the self-confidence of the Church of England. The idea that "Anglicanism" was one of the great historical branches of Christianity, and that Canterbury could be named alongside Rome, Geneva, and Byzantium, turns out to have been, like the Falklands, a mere dream of empire. The Vatican is still a temporal, political power as well as a spiritual one; but it has largely negotiated the painful and sometimes bloody transition from being a state-based power to an international or transnational one. The Church of England shows no signs of doing so.

The idea that Anglicanism could be a "middle way" between Protestantism and popery looked credible to many learned and intelligent men and even a few women only 30 years ago. Now it is shattered. No one, least of all Rowan Williams, thinks that the Archbishop of Canterbury should run the Anglican communion, and no one, except perhaps Williams, thinks that he can. What changed?

Most of all, it was the ordination of women. The question of whether Anglican men could be priests could be, and had been, delicately fudged. It could be understood in terms of 16th century disputes which – like justification or transubstantiation – became almost insubstantial when viewed from four hundred years later. But the question of whether any women, ever, could be priests could not be fudged in that way, and Pope John Paul II was convinced they could not be. (Curiously, it is Pope Benedict XVI, then Cardinal Ratzinger, who is credited with persuading him that he could not declare this infallibly.)

Against this, it became obvious that a large Protestant and evangelical minority of the Church of England did not believe that anyone could be a priest in the way the Catholics, in and out of the Roman church, believe they are, while the larger, much less theologically distinct but still protestant majority believed that women could and must be ordained. They had no interest in the pope's opinions, and, it turns out, no patience with fellow Anglicans who did.

I remember watching one of the interminable Synod debates on the matter with my Catholic friend Clifford Longley, who turned to me half-way through an immensely learned and principled speech against the ordination of women to say that if Rome were to decide in favour of women all of these principles would vanish in an instant. He was right. Essentially, the Anglo-Catholic minority in the Synod wished to assert the authority of the pope without themselves actually submitting to it. When they lost the final vote, and were themselves put to the question hardly any, even then, could bring themselves to submit and most of them turned their abundant destructive energies to fighting over homosexuality instead.

What the ordination of women made clear was that Anglicanism, or at least, the Church of England, was now an ultimately democratic body, which decided matters of even the ultimate importance through a contorted voting system. This change has been reinforced by another: the church has been forced to step down into the marketplace and raise its money from living congregations rather than relying on endowments. Again, this tends to increase the influence of the laity and diminish that of the hierarchy.

Meanwhile, the Roman Catholic church has to all appearances headed in the opposite direction. John Paul II was a notably authoritarian figure, and the present pope acted as his enforcer among theologians. The ban on artificial contraception, believed by almost no one who might actually have to use it, has been used as a shibboleth to ensure that only "orthodox" bishops are promoted. The reforms of the second Vatican Council which had seemed to empower the sort of middle class educated laity who run the Church of England have been repudiated or reinterpreted in the Vatican.

Yet the story is not as simple as it seems, there. The Catholic church in this country is much less disciplined and united than it was in 1982. In part this is a result of growing self-confidence. It no longer feels like a suspect minority. But it has also imported some of the bitter quarrels between left and right and their tone of personal nastiness which have shaped the American church. Those don't look democratic, but in a sense they are, since they proceed from the American laity's self-confidence, which has led both sides to lecture successive popes on what they should be doing. The pope, however, has taken no more notice of exhortations from the right to defend American capitalism and bless the invasion of Iraq than he has of exhortations from the left to be realistic about contraception, or to allow women priests.

What no one could have foreseen in 1982 was the collapse of Catholic Ireland in a welter of scandal and disillusionment – if anyone had then said that in 30 years time there would be no seminaries at all in that country they would have been thought mad. The Church of England, by contrast, has more priests than it can afford, and so finds it very convenient that nearly a quarter are women, of whom less than half are actually paid.

So we're going to hear a lot, in the coming year, from Catholic laity claiming that this visit will demonstrate who is Top Church; and Catholic clergy denying that the thought had ever crossed their minds, or could, in a way that makes it quite clear that they believe it too. And there will be a great deal more, louder, and self-confident atheist protest than there was last time. But I think that all parties will be disappointed. The atheists will be shocked by the degree of public interest in the spectacle and by the persistence and vigour of Catholic intellectual life. The Anglicans will look, and feel, amateurish by contrast. And the Catholics, when the shouting and the tumult has receded, will still have far too few priests, dull bishops, and as their most famous layman, Tony Blair.