Aargh. If it's not murder then why the #3!! would it be wrong??!!
"Murder" is a legal term. You may be confusing the term "kill" with "murder".
Congress and the state legislatures determine which types of "killings" will be defined as "murder".
We "kill" people in war, but that isn't "murder". We "kill" people when the state executes convicted murders, but that isn't "murder". We "kill" people in self-defense, but that isn't "murder". Police "kill" people fleeing from them, but that isn't "murder".
Before Roe v. Wade, some states classified abortion as a degree of "murder", but alas, now it is not "murder", even though it is still killing innocent life.