I have mixed feelings. On one hand, if it takes place between consenting adults..... blah blah blah..... then it's no one's business.
On the other hand, there's a sinister patriarchal (and possibly mysogynous) structure to polygamous marriages that is hard to ignore. In that, a polygamous marriage is like a pyramid - the Supreme Patriarch on top, and his wives beneath him in status. Since there's several of them and only one of him, there would be very little chance that these wives could become equal partners with their husband.
I'm not saying that the monogamous tradition has insured the equality of women in marriage - it hasn't - but there is a much better chance for two people to be equal partners than for several people.
EDIT: Found something of interest - the
Utah Attorney General's report on polygamy. I only skimmed through it, but it does say that polygamy exasparates child abuse and domestic violence in Mormon splinter-groups - partly because of the patrarchal dynamic, and partly because of some their religious beliefs.
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lahimatoa wrote:
So what is so inherently wrong with polygamy? Why is it against the law? What's the difference between sleeping with 9 women at the same time and marrying them all?
On the legal note, I couldn't seem to find any info on how polygamy is damaging as a criminal behavior - unless it involves minors, of course. The Wiki says that since splinter-groups of Mormonism are often not married formally, the only way that they can be prosecuted is by adultery laws, and "unlawful co-habitation" laws.

Good grief - laws like this still exist, outside of Sharia?
In terms of the backlash against Mormon polygamy, Wiki also says:
Wikipedia wrote:
The public revelation of the Church's practice of polygamy led to persecution. Many novelists began to write books and pamphlets condemning polygamy, portraying it as a legalized form of slavery. The outcry against polygamy eventually led to the federal government's involvement and the enacting of anti-polygamy laws.
What the real root of this outcry was...... who knows. My reckoning: people probably saw monogamy as the accepted norm - and that accepted norm may have its roots in the Christian rules on marriage - and any deviation to that was seen as a threat to the fundemental values of society.
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PianoManGidley wrote:
Beyond the Grave wrote:
In polygamy, women are considered to be property.
That's total prejudice. I'm not saying that there aren't people who would act and feel that way, but to say that all polygamists see women as property completely neglects the people who actually devote themselves to all the multiple spouses and truly love them and respect them, as a regular couple would in a monogamous marriage.
Hmmm, possibly. However, the Wiki has something interesting to say here:
Wikipedia wrote:
Currently, an LDS (Mormon) man can be "sealed" for "time and all eternity" to another wife if his first wife dies. An LDS woman can only be sealed to one man - so if her husband dies, she can not remarry in a temple.
Kinda sounds like the husband is a free man in this situation, and the woman is bound for an eternity to her lord and master.
(Yeah okay, I'm being a smartarse. But that rule - and that whole "one rule for men, another for women" dynamic - strikes me as very unsavoury).