Very difficult topic.

My view:
Danger to mother: abortion ok.
Rape: abortion ok.

It is still problematic, but there is no other way.

All other cases: abortion is initiation of force.
Sex leads to pregnancy. The moment you engage in sex you know this is a possibility and accept it. This responsibility cannot be avoided by initiating force IMHO.

The day after pill can avoid much of the problem, in my opinion. I don't consider it as abortion, would like to know if others do, though.