Native peoples of America had no immunity to the diseases that European explorers and colonists brought with them. Diseases such as smallpox, influenza, measles, and even chicken pox proved deadly to American Indians. Europeans were used to these diseases, but Indian people had no resistance to them.
After the free trade agreement, the economy was stable and the unemployment rate was low until 2008. The agreement opened up jobs for not only American citizens, but citizens of other countries in their homeland as well. Sales profits were booming due to the amount of competition as well.
By approval, I think you mean by the delegates from each state had approved it. The problem was that the states themselves had to approve it. That seemed like a cumbersome process, but you have to remember that democracy works on the will of the people and each state had to ratify it keeping in mind that there were still problems: it was not a slam dunk.
