The population in the 1900's was beginning to overflow. In 1875 the United States government had to put a immigration restriction so that no more immigrants could come into the United States. Which ended up leading into the depression. Then later in 1882 the United States government had to put a restriction on all Chinese immigrants because there were too many of them coming over. So as a result you can tell that too many immigrants were coming over into the United States.
Another big factor in why the immigrants should have been restricted in the 1900's is because they would take most of the needed jobs in all of the warehouses. The main reason that they would get all of the jobs in the warehouses is because they would come in large amounts and they were willing to work for very little pay. The places that they lived were usually shacks or a 2 or three room apartment so they wouldn't have many costs to take care of. This also would lead allot of Americans getting angry because it would become harder and harder to find work.
Due to the very poor living conditions that all of the immigrants would live in diseases would spread very quickly. Another reason that diseases would spread is because so many different people from different country's would take very long journeys on a boat where it is tremendously overcrowded. Whenever immigrants would come over they would have to see a doctor. He would ask you "Are you healthy? Do you have any rashes? Have you ever had Tuberculosis?" If he suspected anything, he wrote a letter in chalk on your jacket.
So due to the overpopulation of...