Polygamy is fundamentally inconsistent with our values as a society...
Here is my response:
Lowry's thesis is that polygamy is inherently anti-democratic, but not all polygamy is coercive. There are remedies to the faults he lists (e.g. require that all wives after the first be over a certain age, or that in plural marriages the man cannot be more than 10 years older than his wife if she is under a certain age), as well as some he missed (i.e. the chief problem with bigamy is that one or both of the cuckolded spouses is usually not aware of the other marriage -- require consent of all spouses before approving a subsequent marriage and you have truly democratized polygamy).
In other words, the institution could be reformed in such a way as to increase women's choices. But Lowry does not want to reform it, he wants to abolish it. His aim is not really to condemn it for cause, but to condemn it as offensive to his tradition and to look for cause to justify his bias.
I have no truck with polygamy (more correctly, polygyny -- polyandry, the other form of polygamy, empowers women). I can barely serve one wife, much less take on another (and as any devoted spouse knows, marriage is mutual servitude). But I know that some women who would otherwise go manless in a monogamous society would get married if polygyny were legal. I also know that some women prefer the company of their husband's other wives (lots of available babysitters). Polygamy does not have to take on the bizarre forms that it does when society shuns it and shoves its practitioners into the shadows.
In short, I think Lowry's case against polygyny is intellectually wanting. It reminds me of the case against gay marriage, which is said to weaken real marriage. From what I can see, it merely redefines the word "marriage" in an objectionable way. There is nothing about long-term loving gay relationships that anyone despises -- anyone accept those who despise gay sex first and foremost. Most people would accept the desire of gay couples to formalize their relationships through something like marriage, even if they dislike having the word co-opted.
So to say that such relationships damage other relationships fails for lack of a causal connection. There's a stronger case that heterosexual plural marriages put heterosexual single marriages at risk, for the reason Lowry mentions in his essay: men compete for available women. But this reason founders on the problem of the great abundance of available women (and men).
Close to 40% of American adults are not married. Moreover, nearly 90% of the population age 45 and older has been married at least once. By age 55, that ratio rises to 95%. That tells me that many of those who are not married, wish to do so, but choose not to. Those who choose not to be married do not do so because of a shortage of available partners. Perhaps there is a lack of desirable partners or perhaps they have better things to do.
And the fact is, legalized polygamy would increase the number of available partners. Men and women would be free to join an existing marriage.
Finally, I think we fool ourselves if we think that people forgo their urge for multiple partners by consenting to society's monogamous fiat. People commit adultery and this leads to divorce. In at least some of those cases, polygamy could keep the original marriage intact, and that would, in my opinion, be an improvement over divorce.
Lowry claims that polygamy undermines free choice. In fact, it is the prohibition of polygamy that constrains free choice.