One argument that the pro-Open Borders crowd uses is that we should allow anyone to freely enter the country out of guilt for what we did to the Native Americans. I'll admit I feel bad about what happened to the Cherokee and the Cheyenne and the Sioux and the other native tribes. Thing is, they're not the ones demanding we open our borders to everyone. The people demanding we give them free access to our country are the descendants of the Spanish conquistadors that crushed the Aztec, Mayan, and Incan civilizations among others. Because someone feels guilty about what European colonists did to the native tribes they're supposed to open their borders up to the descendants of other Europeans who committed similar atrocities only on a much larger scale? I don't think so.
If anything I'm amused by the irony of Mexicans being upset that the Anglo colonists they brought in to help them take Texas away from the Native Americans then proceeded to take Texas away from Mexico. Now that's funny.