In general, anti-abortion leaders think the political tide is gradually turning their way. They had already achieved a major legislative success in the last Congress, with the passage of the Partial-Birth Abortion Ban Act of 2003. They are euphoric over the results of last month's elections, including the defeat of Senator Tom Daschle of South Dakota, the Democratic leader who became the symbol for conservatives of Democratic "obstructionism," particularly of judicial nominees.
James Pinkerton had recently written a similar piece in Newsday, headlined “It's the pro-lifers' moment”. Pinkerton says, “This trend cannot be dismissed merely as a victory of Karl Rove and the Religious Right,” he wrote. “Instead, deeper forces are at work: the basic instinct to perpetuate the species.”
The continuing, growing power of the right-to-life movement has many sources, but the most profound source is basic biology: The human species, like any species, is programmed for its own perpetuation. And yet across the industrial nations, the birth rate has fallen. Births are now at or below the numerical replacement level. The once-feared "population bomb," in other words, has proven to be a "population bust."
The pro-lifers who believe this are falling into the is-ought trap: deriving an ought from an is. Our species is programmed to do many things besides ensuring our perpetuation, such as lusting for our neighbours, coveting other people’s possessions, and eating fatty foods. That does not mean any of them is right. The programming comes about because of the way evolution works, under the imperative of survival. Evolution is an amoral process, and to base our concepts of morality on how we are “programmed” is pointless, and would amount to committing the naturalistic fallacy. It fits in well within the creationist framework, of course.
Any argument in which you invoke nature in such a manner is a dubious one. I happen to be pro-choice, but I nevertheless accept that there are reasonable arguments against abortion – the need to perpetuate our own species is not one of them.