The radical pro-life side says The Bible says "thou shalt not kill" so it means abortion should always be illegal.
Yet most of us recognize that killing in a just war, the death penalty, and killing animals for food or what ever reason is not covered by that passage.
I am pro-life but I also think that the pro-life position should be enforced the way it is in the Bible. In the Bible it says that if you cause a woman to be stillborn (i.e. perform an abortion) you pay a fine to the baby's father.
The father has the most natural care for his progeny, so God saw fit to give him the authority over its life. "Abortion" should be legal only when the baby's father accepts it and punished by having to pay him a fine otherwise.