I won’t say much about the shooting of the abortion doctor yesterday, because that subject makes religious debate seem downright reasonable and pleasant by comparison, and I have no interest in kicking over that particular bucket of ill-tempered worms.
I will, however, say this:
A genuine apology doesn’t have a “but” in it. When you say, “I’m sorry, but…”, you automatically negate the apology. You’re either sorry, or you’re not, and when you try to justify yourself in the same sentence as your apology, you’re not really apologizing.
On the same note, when you say “I’m sorry/appalled that he was shot to death, but…”, you render everything you said before the “but” invalid.