I find it a bit amusing to see a lot of conservative Americans giving out about immigrants, when that's exactly what their country was founded on.
This, of course, has absolutely nothing to do with the majority of Americans, who I have found to be highly intelligent.
Back on topic, now.
I think there will be a fairly large demand for immigrants in the US, for the next decade and a half, at the least. A lot of immigrants are willing to do jobs that a lot of Americans would be unwilling to do, and for wages that they wouldn't accept, to top it all off. They are also willing to work longer hours. Unfortunately, a lot of them don't know much a bit worker's rights, and a lot of employers don't educate them. This can often lead to them being taken advantage of.
Because of this, it think there will be a large amount of low-skilled workers coming into the US for the time being. Of course, they will be ultimately overtaken by robots, who will be workers for free.
On the other hand, there are a large amount of very highly-skilled people coming into the US from other areas, a lot of them being developed countries, e.g. Ireland, UK, Germany, Japan etc. These people are there to fill a hole in the jobs market, and their positions will be made redundant only when the education system in America pushes these areas more (STEM), or when robots are incredibly intelligent and capable of such tasks, which be a very long time. As such, I can see these types of people moving to the US for a long time yet.
Of course, as the rest of the world develops, and the skills gaps are filled in by the American education system, the numbers of immigrants will reduce,until it is an unimportant amount. But until that stage, I see there being a large amount of immigration to the United States.
Of course, another thing you guys should remember is the allure of the United States to people from oppressed/poor regions of the world. The US is seem as a bastion of freedom and wealth, and as such, she attracts these people more so than, say, Canada.
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"And when you gaze long into an abyss, the abyss also gazes into you"-Friedrich Nietzsche
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