I think the most brilliant deduction by the left yet is to conclude that to disapprove of something means you're either 1) that of which your disapprove or 2) phobic of it.
There's no such thing as a principled disapproval of any behavior.
You are beginning to get closer to the source of your dilemma, even if you think you strengthen your case, which is, of course, a manifestation of the defective manner in which you think. Let's look at the definition of disapprove:
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dis·ap·prove
   [dis-uh-proov] Show IPA verb, dis·ap·proved, dis·ap·prov·ing.
verb (used with object)
1.
to think (something) wrong or reprehensible; censure or condemn in opinion.
2.
to withhold approval from; decline to sanction: The Senate disapproved the nominations.
verb (used without object)
3.
to have an unfavorable opinion; express disapproval (usually followed by of ).
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We see in definition the way conservatives disapprove, with the notions of reprehensibility and condemnation, reactions of the gag reflex and the stomach, from being made as children to experience disgust and guilt, and in the second two a more reasoned approach that defines out as an opinion with no grandiose claims of absolutism.
Thus we enter the realm of reason where conservatives have trouble going, the gray world of opinion and principle and the internal differences in how these are held. We have principle based on science and reason and truthiness based on ego and dictum, what the bigot absorbs as a child irrationally and remains blind to ever after as his motivation.
The problem we have in communicating with conservatives is that conservatives are motivated to think according to principles that are unconsciously held, are irrational, and cannot be defended, but for the conservative do not have to be defended, are unexamined, are unconscious, and invisible, the bedrock of bigotry.
This is why it is always fun to spin the conservative top by asking one to prove the truth of his principles. He just knows it's so obvious he can't even begin to try. But he will never let go because he fears the world of gray where everything has to be evaluated in the best way the human mind can, by seeking the truth for the truths sake and not to defend the ego.
Take your case. You are a very fine person who believes in the sanctity of human life. This is the truth that makes you certain you are right and the thing you argue to protect. You think that if you lose an abortion argument than human life isn't sacred. This is the force that powers your truthiness. You are absolutely sure that human life is sacred.
But you cannot prove it and so you are just like me. You cannot prove that life is sacred but you condemn those who don't agree when you can't prove your case. Why do you condemn those who disagree because your arguments fail to penetrate? This is just what it would be like for me to condemn you as a conservative. How can I condemn you when I can't ever convince you to see no matter how great my skill because I can never prove you are blind to you.
Now, are you blind because human life is in fact not sacred. In some ways yes, because everything depends on what you mean by sacred and where you go from there. Human life isn't sacred because it's written in a book or beaten into children. Human life isn't sacred because it says so in religion or law or philosophy. Live is the will to live. Live is being and being is love. To live is to love and love is the sacred. It can't be proven except by those who live the definition.
When the sacred isn't rules and principles but love in being, a peculiar thing happens. One becomes a prisoner, one who surrenders the self to the Tao, or if you want, the Will of God and everything that happens is Perfect. To condemn in the world is to deny the will of God. Your job is not to disapprove but to awaken.