Just because you have a moral objection to something doesn't mean it should be illegal.
I'm sort of undecided one way or the other if it's truly a good thing to have an abortion. I don't think people should go out and have unprotected sex and be like, "oh well I can just get an abortion if I get pregnant." I don't think anyone truly has that attitude. The choice to have an abortion should be available to women. Whether or not they should make the choice to have an abortion is up for discussion, but the point is that it is a choice.
I personally very much enjoy having sex with my girlfriend and we use as many precautions as possible to prevent pregnancy. Just because there's a 1% chance she might get pregnant despite condoms or the pill doesn't mean that we shouldn't have sex.
If my girlfriend somehow did get pregnant, there's no way I would push her into getting an abortion. We would have to do a lot of thinking and consider all the options and then make a decision. But the point is that our options should not be limited because of other people's personal beliefs which they want the government to enforce upon everybody. Not all of the country shares the same morals and for those of the opinion that people should not have abortions, don't have an abortion. The government is not here to provide an avenue for you to impose your will on others who are not of the same opinion.
We shouldn't put it on the government to limit people's choices just because it's possible for them to make a bad choice. Freedom implies that people have the right to make choices and to live with the consequences of those choices.