Basically being against abortions. More specifically a misplaced idealism pushed by Republicans with the idea that anything that can become a human is a human, and should have just as much rights. By this logic, every time George W. jizzes all over the oval office carpet he is killing millions.
It is also an excuse Republicans use to blow up stuff; blowing up stuff is just that fun I guess.

Barbara Bush should have had an abortion, instead of doing lines.

A stupid person; it refers to the lack of surface area on an individual's brain. The general thought is that the more surface area (wrinkles, creases, etc.) a brain has, the smarter the person is. Conversely, a person with a smooth brain (no wrinkles) has less surface area and would therefore be stupid.