I'm not being facetious; it's a widely held belief and I haven't been able to find someone who can coherently explain the assumptions and logic behind this thin

I'm not being facetious; it's a widely held belief and I haven't been able to find someone who can coherently explain the assumptions and logic behind this thinking. Here are some reasons against illegal immigration (in general, not only about wages): 1) It's not about the "crime of not being American". It's the issue of not being a citizen of the country, and having no right to be there in the first place. 2) Immigration is not a proper answer to the problems of poor countries, making them better is (and first world countries have a lot to do and a lot to stop doing for this to happen). Immigration is basically being forced to leave your home to find food/freedom/etc. Americans might like to compare it with the ease they leave, say, Texas for New York or California, but it's nothing like it. 3) The encouragement of mass immigration benefits those hiring against the workers of their place. It creates a surplus of labor that lowers wages. You might not care, because you have a fancy CS degree, or you might say "let them improve their skills and market themselves better", but the actual reality if poorer people, lower wages, trailer parks, and unemployment. Yeah, it can be "good for (big) business". But unless if you believe the "trickle down effect", it can destroy whole local communities. I've been all around South Texas, New Mexico, Arizona, California, places with lots of immigrants. I didn't see much "trickle down" effect there. 4) A country exists because it has citizens. Anybody being able to drop in arbitrarily, is not a country, it's a hostel, and can bring huge problems of regarding integration, common values, etc. Now, most "progressive" Americans have issues with the very notion of "common values", but they have the luxury to have it because, basically, all the US shares lots of common values anyway, from the strong belief in the individual, to the respect for the various amendments to the constitution, to the "American Dream", to politically correctness, etc. A gay Democrat nerd in SF has more in common to an Oklahoman redneck than they know (and that they have with a Norwegian or an Iraqi or a Venezuelan). Not to mention a shared history, from the civil war to Pearl Harbor to the glorification of the "wild west", etc. Now, imagine the made up example of millions of islamists coming to the US, and after a few decades, claiming respect for the sariah, beating up women dressed "inappropriately" (in their mind) in the streets, having honor killings, etc. You have the luxury not to think of it, because you are 10,000 miles of ocean away from such countries. Similar things have happened in other countries though. Borders were set up among other things because people like to live differently than other folks and have a place to tout their common beliefs and way of life. Like the, so-called, "American way of life".