The leading argument against slavery during this time in the US was simply that it was immoral, and went against God's will. Another was that it violated the Constitution, and yet another was that it was unsustainable in the South.
The government helped the railroad industry is by granting land to the railroad companies
Religious freedom is the answer.
The Half-Way Covenant adopted by Puritans in 1662 a)made Puritan children and grandchildren partial church members. This was because Reverend Stoddard believed that less people were attending church, because the older generation which did was dying out and the younger generation was more interested in material things than attending church.