Consider the profound philosophical dispute embodied in Mourdock's one inartfully expressed sentence: whether to discourage, with the law and otherwise, all abortions or whether to grant an exception in the case of rape and incest. That is a serious disagreement within the pro-life community, and it is taken very seriously there. There are difficulties with each position. Granting the exemption is morally inconsistent; that fetus there waiting to be born is either an “innocent human life” deserving protection or it isn't, regardless of the sins its father may have committed. But refusing the exemption seems brutally indifferent to the trauma rape victims must endure.
Further consider the even more unfathomable theological dilemma suggested by Mourdock's answer. Are we masters of our own destiny, or are we just living out God's plan? Is God responsible for everything, or does he craft the good and hold us responsible for the bad? Do things work out the way they're supposed to, or is free will capable of changing the plans? Does everything happen for a reason, or do some things just happen? If God knows and cares about each of us, why do bad things happen to good people?
Millions of people have spent thousands of years grappling with such questions. No shallow commentator or glib politician seeking votes is going to seriously try to answer them. It is much easier to mock somebody like Mourdock and feign shock and outrage over the preposterous idea that he is somehow suggest rape is God's will.
Mourdock should have known this – he is an experienced politician, after all, who should have known better than to mix religion and politics. He will probably pay a political price for his remarks. He probably should.