By Alex Kirby
BBC News Online
The most serious division in the Anglican Church's 450-year history now yawns open before the worldwide Communion.
Dr Rowan Williams: In charge but powerless
The split over the choice of the openly gay Gene Robinson as bishop of New Hampshire in the US seems unbridgeable.
For many outside the Church, though, the row over homosexuality seems as obscure as the medieval debates over how many angels could dance on a pin.
And Anglicans themselves can take some comfort from realising they have been living with other splits for years.
The 38 provinces which make up the Communion are all self-governing, bound together by loyalty and (up to a point) by doctrine, not by any constitution.
Some are remarkably rich, others dirt-poor. That has not stopped them working together.
Coping with difference
Some accept women as bishops, others refuse them. The same applies to women who want to be priests.
Many of the provinces are themselves split, with different dioceses (the area over which a bishop presides) taking opposing sides.
In the Church of England this inability to agree has been given institutional form at parish level.
Congregations who refuse to accept women priests are cared for by a sympathetic bishop, not the one who heads their diocese.
But until now all Anglicans, whatever their reservations about their fellow-worshippers, have accepted that everyone is a member of one church.
Eye of the storm: Gene Robinson
That will now change, with more traditional members of the Church denying that Gene Robinson really is a bishop at all, and refusing to have anything to do with him or his diocese.
Many will extend this rejection to include the other US bishops who took part in the service to consecrate him as bishop.
The Archbishop of Canterbury has traditionally been recognised as the leader of the Communion, but it is an odd sort of leadership he possesses. He exercises responsibility without power.
He is in no sense an Anglican pope, and even if the present occupant, Dr Rowan Williams, were tempted to bang heads together and try to drill some sense into Anglican heads he could not do so.
That too may change, because the commission set up in the wake of the Robinson row could recommend giving the archbishop some powers and a new role.
For Church members, one of the worst aspects of what has happened is that Anglicanism has become less united, not more. For them, as in principle for all Christians, Church unity is an imperative.
They argue, rightly, that they cannot expect the world to listen to them if they fail to speak and act together.
Dr Rowan Williams in charge but powerless
So the ultimate prize for most Anglicans, uniting with other churches, is now further from their grasp than it was, and for those who continue to hope for unity with the Catholic and Orthodox Churches the obstacles are profoundly daunting.
The Church is fond of believing that it is one of the few institutions that exist for the sake of other people, not primarily for their own members.
Heterodoxy at bay
This is how it understands its mission to follow in Christ's footsteps and live out its faith in the world.
Much of the world is already bemused at the sight of a Church which makes human sexuality the acid test of orthodoxy.
The row over Gene Robinson has succeeded in reinforcing the walls of orthodoxy. But walls which shut out unorthodox Anglicans may shut out inquiring agnostics too.
Liberal Anglicans fear the church has forgotten that what is supposed to unite it ultimately matters more than anything that divides it.