Father Raymond J. de Souza writes, of John F. Kennedy's 1960 campaign statement, "I believe in a president whose religious views are his own private affair, neither imposed by him on the nation or imposed by the nation upon him as a condition to holding that office":
This was not just separation of Church and state -- which prohibits official establishment of religion by the government. JFK went much further, saying that his religious faith was a "private affair," to be thought of more as a pastime rather than a way of looking at the whole of reality. The wall of separation between Church and state would not be enough; JFK promised to build a wall within himself....
JFK's privatization of religious faith ran counter to the tenor of the times. It would, in due course, be a decisive factor in changing the times. For in winning the 1960 election, JFK demonstrated that one could both profess a religious creed and ignore it for political purposes at the same time.
It's not that Kennedy was the first Catholic who didn't want what he said inside a church to be held against him outside. Nor is that a condition found only among politicians.
But such lack of integrity is supposed to be a moral imperfection (albeit one seen as forced upon oneself by the circumstances of life). It shouldn't be celebrated as a presidential virtue.
Kennedy's personal vice has an unfortunate lasting and culture-wide impace. Fr. de Sousa writes, "Every time a politician says that he is 'personally opposed' to something, but votes for it anyway, it is JFK talking." That may be an exaggeration, but not by much. John Kerry, for example, explicitly invokes Kennedy to defend his own lack of integrity:
To a larger extent than Catholics elsewhere, [American Catholics] have supported and relied upon the constitutional principle of the separation of church and state to guarantee our right to worship and our liberty of conscience. That tradition, strongly advanced by John F. Kennedy in his quest to become our first Catholic president, helped make religious affiliation a nonissue in American politics. It should stay that way.
Many other American Catholics also endorse the Kennedy doctrine, which in effect says Catholic doctrine should play no role in a politician's judgment. (Yes, I know Kerry for one says it means something else, but of the "three particular implications" he says being Roman Catholic has for his "own point of view as a candidate for presidency," the first two are generic non-relativistic humanism and the third is quoted above.)
The effect of this endorsement by many Catholics is unsubtle pressure on all Catholics to accept it. (It goes even further. Not only should a Catholic politician agree that Catholic doctrine plays no role in his judgment, but Catholic politicians whose judgment agrees with Catholic doctrine are politically anathematized.)
Many Catholics who reject the Kennedy doctrine see the neutering of one's judgment by removing all that is uniquely Catholic as a great victory for secularists. It is, certainly, but I think there's something more fundamental at work here. Kennedy declared his doctrine, not at a meeting of secularists, but at a meeting of Baptist ministers.
A man "whose religious views are his own private affair" is not a Catholic in any meaningful sense. By cutting his faith off from community, he necessarily becomes a non-credal Protestant, since Catholicism is by definition a shared and public affair.
The risk to Catholicism in the U.S. is that, in fighting against secularism, it can make concessions to non-Catholic Christianity -- the traditional Protestantism of the country -- that makes impossible a genuinely Catholic character.