When it comes to identifying one’s self with a particular culture, there tend to be guidelines that are a little more vague than the rules and guidelines of a religion. Where a culture could be defined by race or geographic location, a religion is defined by the exact moral practices of a group of people. When it comes to being accepted by a culture, it is typically after practicing the traditions of the culture enough that it becomes like second nature and feels natural to you. However, in order to become a part of a religion, you would have to be tested and formally accepted to the religion in order to be officially brought in to that specific religion. While people of a certain culture might tend to practice a certain type of religion, this does not mean that the god is a part of the culture. Instead it means that the religion is a part of the culture, and the god is a part of that religion. While there are a lot of similarities, there are still a lot of differences as well.
Siri never made any reference to the "Siri thesis", nor was there any mention of it in his New York Times obituary,  in the biography written by Raimondo Spiazzi ,  or in a speech given by Giulio Andreotti on the centenary of Siri's birth in 2006.  He was appointed president of the Italian Episcopal Conference by John XXIII in 1959, and remained in the post under Paul VI until 1964.  He sat on the Board of Presidency of the Second Vatican Council from 1963 until its close in 1965.  He was a candidate for pope—still representing the conservatives—in the 1978 conclave that followed the death of Paul VI, where he is thought to have led in the early ballots before being overtaken by Albino Luciani (John Paul I),  and again two months later in the October 1978 conclave , where he is also thought to have come within a few votes of election.  He was Archbishop of Genoa from 1946 to 1987, and at the time of his retirement he was "the last remaining active cardinal named by Pope Pius XII."