Jewish Jews and Irish Catholics

It is a generally accepted fact that Judaism is both a culture and a religion. This, of course, raises a host of issues. Where does Judaism as a religion end and Judaism as a culture begin? Is Judaism a racist religion? (This is a more complicated issue then traditional apologetics would indicate.) What should be the attitude of religious Jews to those Jews who do not practice Judaism at all or not to the extent deemed suitable by the individual? Who is a Jew? In what sense should Israel be a Jewish state and who should be eligible for the law of return?
I would suggest that these issues have less to do with Judaism in of itself, as a religion or as a culture, and is more a matter of linguistics and the fact that we lack large scale examples of the Jewish religion being practiced in the absence of Jewish culture. We do not have different words for being Jewish (cultural) and being Jewish (religion). This creates an ambiguity every time one uses the word Jew. Furthermore, since we do not have many non-cultural Jews practicing Judaism (People who convert to the Jewish religion tend to take on Jewish culture as well.) we simply take it as a given that practicing Judaism means being culturally Jewish as well. This needlessly confuses the issue and creates problems where none should exist.
Take the Irish for example. The Irish are a distinct cultural group. They have their own country (Ireland), they have their own language (Gaelic), and they have added their fair share of artists, poets, musicians, revolutionaries, scientists and intellectuals to the cause of Civilization. The Irish have their own history of being persecuted both within their homeland, at the hands of the British, and in this country. Today there are millions of Irishmen who do not live in Ireland but live in the Irish "Diaspora" in such places as Boston, New York City and Chicago. In addition to Irish culture, there is an Irish religion, Catholicism. Catholicism plays an important role in Irish history and one can even talk about Irish-Catholicism as a distinct school of thought. An Irishman's approach to Catholicism is not the same as a Spaniard's or an Italian's approach to Catholicism. And many of these differences come out of the distinct Irish experience. For example, Irish Catholicism has traditionally lacked the hostility to nationalism found in other Catholic countries. On the contrary, Irish Catholicism has always been strongly nationalistic. The reason for this was that Irish nationalism was a Catholic movement fighting against the Protestant English. Nationalism in France, Spain, and Italy, in contrast, was a secular movement that fought against the Catholic Church.
While Catholicism plays an important role in Irish culture, being Irish is clearly distinct from being Catholic and even from being Irish Catholic. There are Irish Protestants, Irish Muslims, Irish Buddhists, Irish Jews, and Irish Atheists. No one is going to object to an Irish Catholic telling an Irish Buddhist that he is not an Irish Catholic. This is a fairly simple issue not because Irish Catholicism is so different from the Jewish religion, but because we are used to thinking of Catholicism as something distinct from being Irish. We use two different words to describe Irishmen and Catholics and we are used to thinking about Catholicism outside of the context of Irish culture. The vast majority of Catholics are not Irish.
Since the largest concentration of Irishmen live in Ireland, it is perfectly reasonable for one to look at Ireland as the Irish homeland. It is perfectly reasonable for the government of Ireland to see itself as the protector of Irish culture and of Irishmen throughout the world. If the Irish government chose to offer citizenship to all those of Irish descent and they included non-Catholic Irishmen or people who only had Irish fathers no one would say that the Irish government is threatening Catholicism. Ireland is a secular, democratic country that happens to be 90% Catholic and has the highest per capita rate of church attendance in the Western world. The government is not a Catholic theocracy and it does not exist to advance the cause of Catholicism. Irish Catholics are free to be as Catholic as they wish. They do not have to marry non-Catholics or let them into their churches. The government is free to advance the cause of Irish culture and none of this has to have anything to do with Catholicism.