Thank you, Gelatinous Cube. To clarify, I was looking about the positive and negative aspects of all, though stressing legal (since it will affect legal immigrants, as well, and saying immigrants blandly only brings to mind the image of illegal flood of humans...) immigration on today's USA, since the info will be a base of my case. On the other hand, the topic itself claims (for the affirmative case) that the restrictions on immigrant rights (as a whole) is consistent with the democratic ideals. These restrictions, of course, are still in place. Some are considered basic common sense like no voting until becoming citizens, others are more complicated. I already managed to gather some basic history of immigration in the US from wikipedia, but the issue itself seems more obscure, and much harder to find.