Pope Benedict's third point - which was an echo of his exchange with Habermas - was directed to the West. If the high culture of the West continues to fritter its time away in the intellectual sandbox of postmodern scepticism and relativism, the West will be unable to defend itself. Why? Because the West won't be able to give reasons why its commitments to civility, tolerance, human rights and the rule of law are worth defending. A Western world stripped of convictions about the truths that make Western civilisation possible cannot make a useful contribution to a genuine dialogue of civilisations and cultures, Benedict argued; any such dialogue must be based on a shared understanding that human beings can, however imperfectly, come to know the truth of things.

Can Islam be self-­critical? Can its leaders condemn and marginalise its extremists, or are Muslims condemned to be held hostage to the passions of those who consider the murder of innocents to be pleasing to God? Can the West recover its commitment to reason and thus help support Islamic reformers? These were the large questions that Bene­dict XVI put on the world's agenda at Regensburg.

Three months later, in an address to the Roman Curia, the Pope reiterated his analysis, expressed regret that some had evidently not got the point - and then laid out an agenda for serious interreligious dialogue. Were that agenda to be taken up in a fruitful way, the political consequences would be considerable. Here is what Bene­dict told the senior members of the central administration of the ­Catholic church: "In a dialogue to be intensified with Islam, we must bear in mind the fact that the Muslim world today is finding itself faced with an urgent task. This task is very similar to the one that was imposed upon Christians since the Enlightenment, and to which the Second Vatican Council, as the fruit of long and difficult research, found real solutions for the Catholic Church .?.?. It is a question of the attitude that the community of the faithful must adopt in the face of the convictions and demands that were strengthened in the Enlightenment.