Why would Joseph Smith say that polygamy was God's law?

Before I give you my impression of Smith’s move to enact polygamy and WHY, a little reminder of the social climate of the time is in order. Think of Hester Prynne and the Scarlet Letter that Hawthorne wrote of in the classic novel. Smith was born in a time of heavy puritanical influence. Both adultery and fornication were major no-no’s and they often elicited stiff consequences. So Smith has to become creative when trying to create the all you can eat poon buffet. And also remember the timing of this supposed “revelation” from God. He did not say this right off the bat. Smith waited until the cult was doing well and he had full obedience from the credulous boobs of the time. Then, God not only says that screwing other women is OK, but it is COMMANDED by Him. For those Quormons who wish to get butt hurt and protest, I suggest a good reading of your corresponding supplemental scripture to the Book of Mormon. Smith needed to make polygamy a commandment to avoid the pushback that would come with wanting to do the horizontal bop with daughters and wives. So, he invented a revelation to make it God’s idea. And he cited Old Testament balderdash as his rationale for God wanting the practice restored. That simple. A man using religion to get laid.