The prefect of the Congregation for the Doctrine of the Faith made that point, among others, in a series of interviews with Vatican Radio on the state of affairs in Europe.
"The world's cultures are profoundly adverse to the extreme secularization that has consolidated in the West. They have the conviction that a world without God has no future," Cardinal Ratzinger said.
"Our very multicultural condition calls us to be ourselves ... we still don't know where Europe will go, but the Constitution of the European Union might be a first step toward a new conscious search of its soul," the cardinal said.
Asked if the recent rejection of Rocco Buttiglione as a commissioner of the European Union is the expression of a hostile opposition to Christians' contribution to the building of the Union, the cardinal replied: "It is above all a sign of the way in which the neutrality of the state sphere, in regard to the view of the world, is about to be transformed into a sort of dogmatic ideology."
As a result, "laicism is no longer the guarantee of many convictions, but establishes itself as an ideology that imposes what must be thought and said; for example, it no longer ensures the Christian's public presence," he added.
"I believe it is a phenomenon that should make us reflect," the Vatican prefect said. "What seemed to be a guarantee of a common freedom, is being transformed into an ideology that is turning into dogmatism and endangering religious freedom."
With reference to the struggle for the recognition of Europe's Christian roots in the Constitutional Treaty, Cardinal Ratzinger said: "Undoubtedly, it is important that, in the first place, the presence of our juridical and moral conscience be clearly guaranteed in areas of greater content, something that, in part, has been achieved.
"I think efforts have been made to make the Christian heritage count in specific elements of the European Constitution and its juridical form, with varying degrees of success, according to the cases."
"But I would not regard it as useless or completely mistaken to describe Europe's identity in the Preamble, and to simply state what it is, where it comes from, [and] from where it gets its criteria of judgment," the cardinal continued.
"I would also like to say that the argument which states that in this way a clash is created with other religions, is false. On the contrary, the latter feel assaulted by our absolute secularism," he said.
In comparing U.S. and European attitudes to diverse religions, Cardinal Ratzinger added: "I think that from many points of view the American model is the better one," while "Europe has remained bogged down in caesaropapism."
"People who did not want to belong to a state church, went to the United States and intentionally constituted a state that does not impose a church and which simply is not perceived as religiously neutral, but as a space within which religions can move and also enjoy organizational freedom without being simply relegated to the private sphere," he explained.
On this point, "one can undoubtedly learn from the United States," as it is a "process by which the state makes room for religion, which is not imposed, but which, thanks to the state, lives, exists and has a public creative force," the cardinal said. "It certainly is a positive way."
Cardinal Ratzinger also referred to historian Arnold Toynbee.
"He was right when he said that the fate of a society always depends on creative minorities," the cardinal said. "Christians should consider themselves a creative minority of this kind and contribute what they can so that Europe can recover the best of its inherited patrimony and thus be useful to the whole of humanity."