It is much easier to murder than settle differences peacefully.
There is also the issue of wanting power, if some can wipe out a group of people easily, then other races/creeds/nationalities will likely fall into line sooner than later. Hitler and Stalin did this prior, during, and post WW2.
<span>it arrived on 10th April 1912
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Modern day many immigrants come to the United States from South American countries such as Mexico, Brazil, Guatamala etc.