How many wives did King Solomon and King David have?
More than I do? ;-)
Not relevant, nice try.
How screwed up was their KINGDOM because of it?
Many. And, as far as I know, in the Old Testament, there is no scripture stating that a man is limited to one wife. Of course, in the New Testament, there are several instances where leaders of the church are to be chosen from men who have but one wife. I know of no prohibition against polygamy for the rank-and-file members of the church.
I'm not arguing that they don't have the right within their religion to determine certain moral values. I just wish they would be honest and up front about why and how those values are determined.
How many kings did Israel have at one time?
Short but decent summary of the Biblical treatment of polygamy:
http://www.letusreason.org/Biblexp75.htm
Bottom line, plenty of clues it was not the original design per Adam and Eve, was tolerated but never encouraged in the OT (and often had disastrous consequences), but is clearly being pushed out of acceptable practice by the teaching of both Christ and the apostles. Winked at in the Old Covenant, but outgrown in the New Covenant under Christ. I believe the model of the Church as the Bride of Christ is especially relevant in that regard.
Peace,
SR
The LDS church ended polygamy when the US government threatened to take the Temples.