Although the bill may slightly lower the salary for many American workers, especially scientists, it is necessary. It would allow America to brain drain the rest of the world and in doing so greatly help America's economy. Furthermore, the immigrants wouldn't only fill jobs they could also become entrepreneurs or small business owners and created new jobs.
If you are referring to colonization and how that hurt the Native American population... that is not the same of the current conditions.
America is a country of immigrants. Yet, every group of immigrants is angry when a new group comes in. Though, once the new groups come and assimilate and work and pay taxes and create a great culture... America is better for it.
Your argument is a tautology. "America is better for it," is true, because America is always being redefined as it changes. "The groups who comprised America a 100 years ago" are perhaps not better for it. It is a trivial thing to point out that AmerIndians are quite a bit better off in every measurable aspect of their lives than 500 years ago. Every has improved but the real estate/sovereignty situation.
