Why did Joseph Smith Jr. have so many wives but mainstream Mormons today don't?

Because they finally had to fact the fact that their narrow-minded, backward thinking religious group is NOT going to be the "divine" model of any future society after all, and that Smith really was just some mouthy, randy guy with any eye for weathy and pretty young girls who simply couldn't keep his pants buttoned. They also thought they could keep that realization a secret from the rest of the world, which is why they hurriedly moved enmasse to Utah.

Oops?

And the rest is history.

---EX-Utahan.

You are quoting anti-LDS historians, not Church historians.

Joseph Smith Jr. obeyed God then, and we try to obey God now. Polygamy was practiced when and how God commanded it. God now commands that we no longer practice it.

The Book of Mormon rejects polygamy, unless it is commanded by God to raise up children. In Joseph Smith's day, it was commanded by God to raise up children.

The mormon church split up into two groups after they were push out of their homeland for practicing polygamy. There are the modern mormons today who are monogamous, and there are various sects in America who still practice polygamy (FLDS) against the law, and who they believe are obeying the word of god.

Modern US legal system. That's why.

First of all it was likely more than 30, but calling them "wives" is somewhat misleading since they were dynastic sealings and only a few of them could even be cause for speculation that they were joined together as husband and wife (a lot of them were married to him after he was dead) - so those aren't really "wives" as one would call them.

Brigham Young and other leaders did have multiple wives, and there was a place in it for the women. At the time a woman couldn't really live without a man (jobs didn't cater to women), so it was a means of providing for women. Take the case of Brigham Young, he had children with about half of his wives, the other half were older women, widowed or otherwise in need and "married" to him for support.

The big reason is that the church renounced polygamy in the late 1800's - but beyond that back in the day of Brigham Young I can see how it's easily justified as being a way to take care of women and children and done in their interest, whereas today it's most frequently done in a way that shields them from outsiders and education and runs off the young uneducated boys so that the men won't have competition. Therefore polygamy today is very different than what it once and that makes it hard to compare.

Ask the FLDS and other small Mormon sects who still practice polygamy.

Every LDS President and prophet from 1830 to 1945 was a polygamist.

dont take it seriously people. the questioner here is just pointing out how corrupt the mormon founders were. this valid point is the sexist controlling founder that used power over people to control them. they change their "scriptures" constantly in the past to their needs. they receintly changed their secrets in their temple rites because of the outcry that today's people see in it. They spend hugh amounts of money to buy up businesses and land to "own" everything.

receintly i went to salt lake and was blown away at how run down and crime ridden it is. absolutly not somewhere i would want to move to.

they still do

Joseph began Celestial Marriage, or plural marriage at God's command. That continued until 1890 when the laws of the land ran their course against the church and God relieved us from that commandment. He stated that he would hold the government responsible for our not being able to obey or continue any further. Thus, we no longer practice plural marriage. The general rule has always been one man and one woman married for eternity. If God desires to raise up a generation to himself under the plural marriage rules, he commands his people. That is what he did in the 1830s. By the time 1890 came around, the purpose had been served and the general rule returned.
That was then and this is now. The times are different and some rules have to be modified to meet current circumstances.