skeptoid,
You should read the article. The problem is far more serious than simply castrating the guilty as a means of punishment. Each and every American should not only be disturbed by this, but outraged that America has arrived at such a place in history in which this abhorrent behavior threatens to “go mainstream”.
The progression of discourse tends to be:
1) No one even thinks to talk about X.
2) X is mentioned, but only derisively and in passing.
3) People go on for hours about how horrible X is.
4) Someone actually stands up for X, but is generally castigated.
5) People come up with increasingly sophisticated arguments about why X is horrible.
6) A minority of people come up with increasingly sophisticated arguments for why X should at least be tolerated, but they are generally dissed.
7) A minority of people come up with arguments why X is actually a good thing, or how some people have to do it.
8) A majority of people believe that X is horrible, but it can be tolerated so long as no one talks about it.
9) A majority of people believe if someone wants to do X, then it is OK by them.
10) More and more people start taking a stab at X just to see.
With incest we are somewhere around step 4. Right now it seems as if we are winning this cultural battle, but we are just at step 4 on our inevitable decay toward step 10, which is where I currently believe we are at with regard to homosexuality and its associated practices.
If there is no generally agreed upon downside from a purely materialistic point of view, then mentioning X ultimately leads to tolerating, and even encouraging, X for those who wish to engage in it. If all you have to do is abort any physically defective children that result form incestuous unions, then over time society will agree that it should be tolerated so long as all parties are consenting.