abortion and halacha
To summarize, Jewish law does not hold (as much of Christianity appears to) tha life begins at conception; rather, human life begins at birth. (Specifically at crowning, as I recall.) The torah covers causing the death of a fetus; it's a property crime. Killing a person, of course, is not. So abortion is permitted under Jewish law. Not desirable, but permitted.
Now here's where the halachic problem with the agenda of the far right comes in: under Jewish law, there are cases where abortion is mandatory. It is unambiguous that this is required to save the life of the mother; the rabbi generally agree that it is also required to preserve the health of the mother.
Most pro-choice folks (certainly myself included) argue on the grounds of individual liberty, but the author of this article points out that as Jews we should be considering the halachic issue, too. The rest of this entry is me talking, not the author.
If Bush gets his way (through legislation or by stacking the Supreme Court), we could end up in a situation where national law forbids the correct practice of our religion, specifically as regards to how we treat other people. I've been trying to think of an analogy for Christians (staying away from murder because it's emotional), and the closest I can come up with is: suppose the government required you to bear false witness against your neighbor, with the result that he would be criminally or economically ruined. (And if you think that can't happen...) That's a violation of one of the ten commandments. Would you be outraged? Would you heed that law? Requiring the Jewish community to stand by while an actual life is ruined in favor of a fetus is kind of like that. A Jew who does that violates laws (both between man and man, and betweeen man and God) that we take every bit as seriously as Christians take their laws that say life begins at conception. But Christians do not sin if they fail to prevent an abortion; we do in some cases if we fail to perform one.
If religion has no bearing on government, then the anti-abortion lobby has to rework its arguments. If religion does have bearing on government, then all religions must be considered, not just the one most popular with lawmakers. Some of the founders of the country may have been Christian (many were Deists), but this is not a Christian nation. Not then and certainly not now.

no subject
I don't think the issue being discussed was treatments of a condition, where the treatment might/would indirecltly harm the fetus, but rather conditions that make it impossible for a woman to survive a pregnancy.
For example, the *only* treatment for pregnancy-related eclampsia is to terminate the pregnancy. In many cases it is possible to deliver a severely premature baby, who may live or may die - I think we can both agree that delivering a baby who might or might not live is not an act that deliberately takes a life. But what if the fetus is not yet well-enough developed to have any chance at surviving? Do you risk a woman with pre-eclampsia's life by keeping her pregnant for another week so that her fetus has a 10% chance of living?
no subject
So, my answer, which I believe to be in line with Catholic teaching, would be to do what you can. Do what you can to ensure that the mother can keep the baby, be it bed rest at home or in the hospital as necessary because that is still the child's best chance for survival. If that fails, deliver the baby and do what you can to help it to survive. In that situation if you've done what you can and the baby dies it is extremely unfortunate but you can't be faulted for it.