We have changed the legal traditions and practices surrounding man-woman marriage (especially with regard to divorce and child custody) far more in the past 80 years than would be required to make poly marriage workable.
Downvoted for "Disingenuous". If you disagree with a point, it is generally better to just counter it, than to accuse the commenter of making it in bad faith.
ETA: Downvote removed, following removal of the accusation.
A thought occurred to me today as I skimmed an article in a rationality forum where the subject of gay marriage cropped up; seeing as the issue has been hotly contested in various public fora and especially the courts, what about poly? After all, many if not all the arguments for gay marriage apply to poly marriage as well.
Questions for LWers who are currently in a such a relationship, or have an opinion to share:
Do polies want to marry each other or do such relationships not lend themselves to permanence above a threshold of partners? Should polies campaign for the right for a civil union anyway? what are the up and down sides of this? etc