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It doesn’t map on in obvious ways to what you see in Europe. In Denmark, for example, immigration was a political issue. When it turned out the people wanted to restrict immigration, the left of center government supported “far right” immigration restrictions.
In America, a large part of the left sees immigration as a moral issue, not a political one. When Trump was first inaugurated, the left refused to even accept Trump as legitimate because of his opposition to immigration. Hilary Clinton called his supporters “deplorables” and said he was “illegitimate.” This was long before any of the bad things he did.