Catholicism is steadfast. There are simply some things — many things — that are non-negotiable. Whether or not I agree with all of those particular positions, I admit that I admire the Church’s willingness to take stands on issues that it knows will not easily or immediately win converts and may in fact drive some people away. It doesn’t seek popularity; it seeks truth. It is, in other words, the exact opposite of contemporary politics, where compromise is everything.
Yet the Church is not unreasonable. The Church teaches abortion to be a sin so grave as to warrant immediate and automatic excommunication. However, far from being absolutist on the issue, the Church admits several reasonable exceptions:
To actually incur the excommunication one must know that it is an excommunicable offense at the time of the abortion. Canon 1323 provides that the following do not incur a sanction, those who are not yet 16, are unaware of a law, do not advert to it or are in error about its scope, were forced or had an unforeseeable accident, acted out of grave fear, or who lacked the use of reason (except culpably, as by drunkenness). Thus a woman forced by an abusive husband to have an abortion would not incur an excommunication, for instance, whereas someone culpably under the influence of drugs or alcohol would (canon 1325). (Source)
Even the excommunication for abortion is not the final response to the act the Church so consistently teaches and campaigns against. Like all sins, it is something that can be confessed and forgiven, with absolution for the excommunication.
The pro-choice response to this would likely be, “Well, the Church shouldn’t excommunicate for abortion to begin with; it’s the woman’s body and the woman’s choice.” That strikes me as more unbending, more absolute that the Church. For pro-choice advocates, the Catholic Church’s preaching against abortion is always and forever wrong, and as such unforgivable; for the Catholic Church, the purposeful ending of a pregnancy is always and forever wrong, but it is forgivable.
The Catholic Church’s reasonableness is not limited to social issues. Its theology is circumspect as well. One of the most troubling doctrines of Christianity is the existence of hell. An extreme Protestant position always struck me as unreasonable: individuals who have not heard of Jesus and his sacrifice are unquestionably condemned to the flames, thus adding great impetus to proselytization. The Catholic position is much more nuanced: it simply states that, apart from saints, humans can’t know who will be condemned and who won’t. While not a pluralistic theology (i.e., all are saved no matter what), it is much more respectful of the simple fact that it would be God, not humanity, making such decisions. It’s a frank admission of a quirky religious agnosticism.