Well, in reverse alphabetical order:
Yawn: Firstly, I am bemused at how 'fragmenting' posts is poor etiquette. I already presented an overview of my argument, so it would seem sensible to be precise about what you are answering (although it admittedly doesn't allow one to let loose a full range of rhetorical fireworks - I try my humble best.) Further more, it seems to be a relatively common habit. Why not mention it when me and Nathan were doing precisely this for several pages in the 'Science and Christianity' thread?
It seems that I am being misrepresented (perhaps through my own lack of articulation,) so I will try and restate my argument again, as it seems people consider I think disabled people should be killed because they are a burden on society.
Bluntly, until the later stages of pregnancy, I don't consider fetus' to be much more people than cancer tumours. Throughout pregnancy (and early childhood) fetuses/babies do not have much in the way of higher mental functions, or anything else we regard as human except, crucially, the potential to grow into one given sufficient time. It is of course by no means certain that a given fetus will make it all the way to adulthood (although with modern technology it stands a pretty good chance after a few months gestation.) Important also to this moral calculus is what sort of person it will grow into - needless to say this is hard, but in the case of disabilities we have a better tell, and this is probably the bit which is provoking the fireworks.
Whilst it is cute to say that disabled people have their own 'special' gifts to give to society, I think that is just silly. There is no reason to think that disabled people are worthless, particularly as western society doesn't really need many people to be physically active, there is no reason why someone with a disability can't be, amongst other things, capable of intellectual brilliance, etc. They can contribute in some fields just as much as anything else, but I doubt they out perform the able bodied in these fields. Disabled people are hardly all lesser people whom are burdens better off gotten rid of, but (as the name suggests) they are not capable of doing all the things able-bodied people can do. In a good deal of cases this difference is trivial, but were we in less fortunate circumstances (say, fighting for survival with scarce food), it would be the more dependant people who would be sacrificed first, and it would tend to include the disabled, as well as the elderly, injured, and children. It is only a minor difference in terms of the moral status of a fetus, but it is one that should be remembered, nethertheless.
We obviously are not in such a situation, and the welfare state should have a patent interest in maximising the wellbeing of all citizens, and so it is in the states interest to maintain those who have disabilities (or indeed chronic conditions) because of the contribution they make to the state (in some circumstances, depending of course on the severity of disability), or, more altrusitically, because they lead happy lives and similarly are valued by their families, which the state should hopefully have an interest in perpetuating. I don't see why anyone would want to force abortions on children who will be born disabled if the parents want the child - the only possible circumstance I could see this being permissible is if the condition is so severe that the child will lead a short, miserable and painful life - in other words, is better off dead.
Returning to topic, the difference in disabled or able fetus' (unless the disability is crushingly severe) is minor, and doesn't matter much to the moral status, however, there is the mother, who might not want this child. Unlike the fetus (or indeed the baby) the mother is a fully grown human being, and so, basically, what she wants over rides what a potential human may or may not want (it is, after all, silly to presume that a fetus WANTS anything, including life.) So, she basically has a right to stop pregnancy whenever she so chooses (here is the important bit) regardless of whether or not the fetus is disabled.
Unfortunately, it is not as simple as that. Ideally, we would like to remove the fetus and support it outside the mother, but that can't happen, so the fetus needs to be killed or carried to term. But, until the latest stages (where it is considered better for the mother to carry the fetus to term and give it up to the state), the mother still has the right to an abortion. Ironically, contrary to what people think, I don't believe the 'deadline' should differ between able and disabled fetuses, merely that it should be set a) very late, and b) extended only in the interests that the pregnancy is the risk to the mothers health, or that it turns out that the baby is going to suffer some terrible affliction.
The point is, is that quite a lot of people have stated that they would prefer to have an able child, and thus would want to abort one that had disabilities. I can appreciate the reasoning for this, and, through what I said above, I don't have any objection to them having an abortion up to a quite late stage on these grounds - why bother making them lie and come up with another reason why they don't want a child?