In a nation of immigrants and their descendants, why was there so much hostility towards more recent arrivals?

Second paper topic

Acceptance of immigrants into the melting pot of America is an important national myth. As with many myths, there is truth to this, but exploring immigration reveals that the story is much more complicated. We can see evidence of hostility toward immigrants throughout much of American history, into colonial times, and this hostility seems to only increase as we progress through the course. In a nation of immigrants and their descendants, why was there so much hostility towards more recent arrivals?

You should plan to write a cohesive, formal essay, at least 1300 words, in which you develop an argument and advance it through making points and using evidence to back them up.

The formatting is the usual – double-spaced, standard margins, normal sized font (11 or 12 point, depending on which you choose) and so on.