Ponder this: What if it was a crime to cheat on you love one?

Answers:
There would be a lot less cheating.

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Then there would be a lot of people in jail.

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people would still do it

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everyone would be in jail unless all the cops in the world were jailed first so there was no one to arrest anyone.

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we would all be in jail

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Then I would have multiple life sentences! HEYYOOOHHH! I am just kidding...

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The the govt would have the authority to evaluate and punish violation of private promises -- and worse, it would have the authority to evaluate whether one person "really loves" another or not .
I'm sorry, I oppose fascism and govt control like that.