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Google "slavery pro-choice" and you'll discover that anti-abortion activists have attempted a very similar rhetorical comparison. The slave states were, after all, "pro-choice." Landowners had a right to choose to own slaves and states themselves had a right to choose to allow it. Do you see interesting congruencies in this or just plain stupidity? Presumably the latter, if you're pro-choice. The former, of course, if you're stridently anti-abortion.
Comparing similar rhetoric in situations that are entirely dissimilar is tempting, but yields little useful. People will adopt whatever reasoning best reinforces their previously held opinions. Reactionaries, by definition, say reactionary things. The so-called global warming sceptics will tell you that alarmists say alarming things; thus today I found global warming being compared to witch trials, by a particularly creative Australian sceptic. Interesting congruencies? Not really. Apples to apples, please.