Responding to Julian Sanchez' comment: perhaps I have misrepresented the thrust of Ross' point, but it is clear to me at least that he is using valid terminology. The eugenics movement was multifaceted and we are certainly not seeing an equivalent repetition in genetically selective abortions, done by individuals for particular reasons. However, considering that the overall aim of the eugenics movement was to create a genetically superior evolution, 1-3 are somewhat secondary to the true spirit of eugenics. It seems Julian and Ezra are expressing aversion to guilt by association, since they don't seem to question the goals of eugenists per se (except perhaps insofar as they believe some of their particular genetic goals were based on irrational or immoral assumptions).
Of course since abortion is the selective mechanism it is egregious regardless of whether the motive is with an eye to eugenic aims. But this should serve as a reason to highlight the additional immorality, not as a reason to ignore it in favor of the larger trangression. To use a religious metaphor, sin has its own gravity. When one's aims are perverted, destructive means more easily tend to follow. The aims of modern, "enlightened" eugenists to create a stronger, healthier and more viable offspring (by democratic mechanism) are perverted, disordered ends. These ends reinforce pro-choice orientation and other trangressive, immoral stances, such as the sterilization of those with Down syndrome, which happens to this day. Gattacca is still science fiction, but if it is possible it will begin with such a trend. We already here people talking about eliminating babies with "gay genes".
Yes, that the mechanism is abortion is the most atrocious aspect of genetically selective abortions, but the fact that abortion is increasingly motivated by modern eugenic aims is insidious in itself.
Addendum: Julian has converted his comment to a post with an addendum. He writes:
"Update: LP in the comments suggests that one can interpret "eugenic" motivation as a factor that might make the already-bad practice of abortion even worse by analogy with hate-crimes legislation, insofar as it may signal to adults with certain genetic conditions that they are widely regarded as undesirable. There's something to this, but I don't think it was Ross' argument.
An additional argument occurs to me, which is that if you're persuaded that abortion is bad, then anything that increases the number of abortions is also bad. And you might imagine that, over time, a "eugenic mindset" will tend to emerge, such that people will come to regard it as normal (and perhaps normative) to routinely abort all but the "best" fetuses.
Here, though, the anti-abortion argument and the independent anti-perfectionist argument may cut in different directions. Because as technology improves, genetic engineering will be a more attractive way of producing desired traits and eliminating disfavored ones than selective abortion, and so the former should to some extent serve as a substitute for the latter."
My point has something to do with this "eugenic mindset", but not primarily because it may encourage abortion directly, though that would be a horrific consequence. The more general problem is that eugenic ends, even when pursued by voluntary mechanisms on oneself via genetic engineering, are disordered ends and will naturally engender other disordered ends and means. One example of this is the new trend in genetically selective abortions, most of which would presumably not have occured had the couple not known their child was "not normal". Even with genetic engineering we can already see some of the consequences that may follow, including a new racism, an obsession with youth and virulity with many unhealthy consequences, including partial destruction of the family, genetic warfare, and many consequences impossible to foresee directly.