I'm a little amused by this exchange, since ideologically I'm probably somewhere between the two of you. There was indeed a wholesale slaughter and mistreatment of the native populations in America during the 1800s, and by today's standards, much of it would be considered unconscionable.<p>But mostly, I'm interested in the facts of history, so I should point out that the "illegal" Mexicans are "discovering" land which <i>used to be theirs</i> in the first place. The current United States western and southwestern were already occupied by Mexico, up until the Mexican-American War, which ended with the United States forcibly buying the land from Mexico for a rather cheap sum.<p>It's also worth pointing out that the United States government probably already had an inkling of the natural value of California; the great California gold rush began less than a year later, and had that territory still been occupied by Mexico, it would have dramatically changed the balance of power in the Americas.