To disestablish the Church would mean that this country no longer has a state religion. At the moment the state religion is the Church of England which, as we all know, was established by Henry VIII to remove England from Papal control and influence.
By doing so, he intended that no monarch who is a Catholic would ever legitimately reign over England.
What of the reign of Bloody Mary? The only explanation is that Henry's last will and testament, which was made on the basis of blood relationship, gender and seniority of his various children by his various wives, omitted to take into account the fact that his eldest daughter, born of Catherine of Aragon, Catholic through and through, would become Queen when his sickly son Edward died young.
No doubt the one who drafted Henry's will would have lost his head had Henry been alive to accuse and find him guilty of professional negligence. After Mary died the succession passed to Elizabeth. If she had any inclination towards Catholicism, she in her wisdom knew it would no longer be politic to be open about them after her sister's Catholic reign had so traumatised the country.
If you disestablish the Church, then it means that those who become monarchs can be free to embrace any religion they please WITHOUT making it the state religion. In my opinion it would be a good thing, precisely because you never know which religion a monarch might embrace and give the British periodic opportunities to discuss the relative merits of different religions. Catholicism? Islam? Mormonism? Buddhism? Who knows? But it would be a private matter and vary from monarch to monarch.
If Prime Ministers who wield real power are allowed to have freedom of faith, then I see no reason why a constitutional monarch with no political power should not be allowed to do so.
Because of this, the objections raised against a Catholic succession no longer apply.
Since it is Prime Ministers who hold power, I would be more in favour of an Arch-Philosopher (who should be preferably an atheist in order that they have the requisite intellectual flexibility and can be more easily seen as non-partisan) to serve as the Conscience of the Prime Minister. As a species, it is in fact Prime Ministers who are most in need of an Official Conscience of flesh and blood that is rooted in philosophy rather than a child-like belief in an invisible magic friend.
It has been pointed out by the Buddha that belief in God is but another form of attachment, which, as all Buddhists know, is the root of all suffering. The goal of being a Buddhist is to achieve enlightenment. Enlightenment, as we all know, equips those who have it with an indifference to suffering and death without the need to believe in the existence of God.
As a nod to Plato's recommendation that society should be ruled by Philosopher Kings, an Arch-Philosopher would be just the thing to replace the ineffectual and redundant position that is currently the Archbishop's. After all, it is not the constitutional monarch that is in need of a spiritual adviser, but the Prime Minister who is in need of a moral guide and a philosophical adviser!
