I thank Mr. Paul for his candor about the role that he feels the Federal government should assume in protecting unborn children. Actually, it would be more accurate to say "should NOT assume". In a nutshell, he believes that abortion is murder, but he also believes that the Federal government has no role in making any decisions regarding the same. It "should be left to the individual states".
He's a big advocate for states' rights over federal obtrusiveness. Generally, I'd agree with him, but not here. There are matters that trump even states' rights - such matters are the rights of "life, liberty and the pursuit of happiness", and IN THAT ORDER! One of the prime functions of government is to protect its citizens from unjust aggression - all of its citizens. If abortion is outlawed in one state, but embraced in next state, that means some citizens are imperiled while others are protected. That's not morally acceptable by any stretch of the imagination - and perhaps a violation of the 14th Amendment to boot.
Some might say, "hey, if you don't like a state's law, you can move to another", with regard to abortion. Oh really? Let's try a little common sense here. The person who has the most at stake in this question, the unborn child obviously lacks the ability to "just pick up and move". He or she deserves no less protection than does anyone else.
This is one primary reason why I believe this "libertarian" position is immoral and is not compatible with true conservatism nor Christianity.