It's not the pregnancy itself that the liberal social values party you refer to are commenting upon. Palin is an avowed Evangelical and all which that implies about her stand on premarital sex et al. Now, as is usually the case when perceived transgressions involve a family member, she is adoptng an accomodating tone with words of love and acceptance. So far, I haven't heard or read of her fellow Evangelicals or other religious people on the right questioning Palin's home environment in which such a pregnancy has happened. I bet that if such a pregnancy happened to one of Biden's daughters it's occurence would be laid at the door of her liberal upbringing.