The Pope publishes its first encyclical, Deus Caritas Est; for an overview have a look here. For the whole text, here.
Of particular interest is the distinction between Charity and Justice. In Ratzinger's mind, the action of the Church is geared towards charity, which is seen as a responsibility for the Church. Justice, to the contrary, is a political value at the centre of public life, and distinguished from the life of the Church.
But is it really? The Church has many times intervened (improperly in my view) in public debates and has never taken the responsibility of its words/actions. It is a far too comfortable position, and has to be reviewed carefully. Either the Church carefully respects the boundaries of politics, or it (the Vatican) bears the responsibility for its inconsistent doctrines before the whole world of faithful people.
Consider the following excerpt from the encyclical:
"The Church cannot and must not take upon herself the political battle to bring about the most just society possible. She cannot and must not replace the State. Yet at the same time she cannot and must not remain on the sidelines in the fight for justice. She has to play her part through rational argument and she has to reawaken the spiritual energy without which justice, which always demands sacrifice, cannot prevail and prosper. A just society must be the achievement of politics, not of the Church. Yet the promotion of justice through efforts to bring about openness of mind and will to the demands of the common good is something which concerns the Church deeply."
This is a deeply ambiguous position. First, it says that politics is the forum for justice and not the Church (fair enough). But then goes on saying, that the Church is going to intervene as it wishes to promote justice, that is its OWN version of justice which may well be, and often is, in CONFLICT with the conception of justice that a polity brings forward (just think about the aids question in Africa).
So, once again, the Vatican would like to catch two birds with a stone. First legitimise itself vis-a-vis of the State and the people; then claim a role in politics, without having to bear the responsibility for it.
As far as I can see, the Vatican should intervene in politics as much as it wishes on the ground of its freedom of expression. But in all honesty, it should simply acknowledge that what it is doing when it intervenes on matter of abortion, research on embryos, euthanasia, and so on and so forth, the Vatican is SIMPLY doing politics as any other lobby.
There is no easy answers to those questions, that is clear. But the answer for this world can only be political. Ratzinger and the Vatican have no privileged position in those debates; if they join in, they simply must engage their responsibility and avoid hiding behind the smoke screen of the separation of Church and State.