The thing about abortion, I think, is that it's a medical procedure; you can't force a person to undergo surgery, for example (except maybe under exceptional circumstances after a long legal action?); so you can't force a partner (er, the woman, obviously) to have an abortion.
But, at the same time, you can't deny medical treatment on the basis of another individuals opinion or beliefs. Whilst it takes two to create a child, there's only one who carries it; and I think the legalities of abortion (or rather who can give consent/seek it) are concerned with that medical situation, rather than the various conflicting moral views.
(Whilst I don't like or approve the idea of abortion as an easy 'get out clause' for unplanned preganancy, I think that's always going to be the inevitable consequence, because every system is open to and will be abused; look at the NHS, benefits services for example. But I wouldn't illegalize it, because I think that choice is important)
Paternal rights/liabilities.... I think there is still a hangover of the old attitude that 'a womans place is in the home', so there's an ingrained expectation that the father must support the family.
I'm not sure if that's always fair, of course; the problem is that you have 2 conflicting things here - 1/ the mother aborts against her will (which IMO would really be a violation of personal rights, even if she's grudgingly convinced to do so) or 2/ the father has to pay for the child he doesn't want.
I believe that the 2nd is a better option (by no means ideal), because it involves a financial 'penalty'; the 1st entails a physical and probably psychological effect which IMO would be more damaging on an individual basis. Obviously it has to balanced against the honest wish of the father not to have a child, against him simply running away from his responsibility.
Oh, and single murder depending on the developmental stage of the child. I'll admit that I'd like to see him go down for a double murder cos he's clearly a twisted ****, but from a detached perspective I don't think you can change the legal age of 'life' around to suit the situation.