Protecting the Unborn

When should we protect the unborn? Oklahoma recently passed a law allowing a mother to use deadly force to protect her unborn child. This stems from an incident where the boyfriend of a pregnant woman punched her in the stomach and she stabbed him to death. The babies (4) died and she was convicted of manslaughter. Talk about irony!!! This same mother could have aborted these four babies and not faced any criminal charges at all! Now I agree with this new law to protect the babies, but how is it that a woman can kill to protect the same babies the law gives her the right to kill? If we don't consider the life protected when it is conceived, then why bother at all until the baby is born. After all...it is just a fetus...right? We are a sick people.