I'll repeat myself. There are no jobs Americans won't do, just jobs Americans won't do at that wage. An American working in a meat packing plant at $8 an hour is not necessarily white trash, or even white - look at what has happened with unemployment among young black and Latino men in areas with high illegal populations. An American single mother working as a hotel maid for $7 an hour is not necessarily a bad person, just a person with few job skills. That $7 an hour job might be the difference in her working, with some pride and self-reliance, and her raising her child on welfare. And if she does that job well, she might well go on to a better job. Very few people who earn minimum wage still earn minimum wage years later. It's easiest to learn job skills in school, but experience works too.
Just because someone earns little money or has no job skills to protect them from competition with illegal immigrants doesn't make them bad people, and it certainly doesn't make you superior to them. There are a lot of reasons why people don't pick up marketable job skills - a divorce at home might make a kid so miserable he flunks out of school. A kid forced to move very often may fail to get a useful education simply because of social pressures and unhappiness. A girl might get pregnant and drop out to keep her baby. A kid might drop out of school because he has to work to support the family, or to follow a dream of being a musician, or because he gets hooked on drugs or alcohol. A kid can get diagnosed with mental illness or mild retardation or a learning disability and not be given access to the advanced educational opportunities needed to get job skills safe from illegal competition. Some kids drift through school not learning much simply because they have no role models; nothing in their world convinces them that education and hard work are desirable and useful things, at least to them. Some kids live in school districts where the kind of education that allows one to easily go on to earn valuable job skills is simply not available. Kids in these situations who don't learn valuable job skills are necessarily bad or dumb, they just aren't exceptional enough, or lucky enough, to overcome the odds stacked against them.
Many kids didn't learn a job skill now in demand because they expected to work in a local factory or mine - then that factory closed and went to China, that mine closed, leaving them with job skills that no one wanted. (That applies even in engineering - any idea how many aeronautical engineers went from $100K to $12K in one year?) Some people committed crimes and did jail time, or are registered sex offenders, and unskilled labor is all they can get. All these sorts of people are very vulnerable to sudden increases in unskilled labor, and illegals are the worst because employers can treat them worse, require more from them, give them fewer or no benefits, in addition to the wage lowering effect of any increase in any particular labor pool.
You need to get off your high horse. Very few of us haven't made some mistakes, some bad choices, in life. And no job skills are completely safe - new methods of outsourcing are always being tried, and existing industries are continually becoming obsolete. Just because you may have earned rare and valuable job skills doesn't make you a better person, just a more valuable one on the job market.
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