I don't think that reactions to illegal immigrants can be fairly compared with those towards the LGBT community. Those who judge gays et al. do so for various reasons, be it religion-based, fear-based, whatever. They are for moral reasons, even though LGBT freedoms would not have a significant impact on their life. Illegal aliens, though, are a different issue. First off -- "illegal." They entered the country in an illegal matter, having eschewed the nation's laws for immigration. What makes people more angry about the problem of illegal immigration is that often, the government doesn't seem to care to do anything about it. While some people may dislike illegal immigrants because they are inherently racist, I can assure you that most who foster resentment do so because they are angered by the injustice towards those who DO follow our laws to enter the country, and additionally simply because, why do we have laws that are necessary for the continuation of our country if the government fails to enforce them? Rest assured that most Americans nowadays that are racist towards Hispanics are that way because they are angry about the illegal immigration problem, and not the other way around.
One final thing (and I'm sorry that this is so long-winded; I am very sleepy.): No other world power is experiencing such a ridiculously out-of-control immigration problem. In Europe, which is on the whole much more liberal than the U.S., people are just shocked when they realize how so many people want to grant free access to Mexicans crossing the border. It's just ludicrous and illogical.
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