But see - you're assuming that everyone who believes life starts at conception (or even at the first heartbeat) believes that slavery is okay or gay people shouldn't have the right to marry, etc. That's just not true. There is lots of nuance that has to be considered here, and not all people who believe in one thing believe in everything else you listed. They're entirely different conversations - you connect them only because extremist, biblically inaccurate people like Sean Feucht scream them from the top of his lungs, but not everyone falls into his camp of extreme Christian ideology (I could even argue it's not very Christian-like).