What are the main pros and cons to immigration in north america?

One of the biggest cons of immigration is the living conditions. Immigrants were poor and came to America with nothing but the clothes on their back. They were force into small environments because so many people came over from countries.
Another con is the treatment at work. They were forced into harsh working conditions as well some didn't get breaks and didn't get to sit down until they got off. Their children had to work as well to support the family.

A pro is that they brought cultural diversity to America. Some made it big and got better jobs which is why America is where it is now. For most people in barge of businesses it was good because they had more workers. It depends on which side you look at it from