Correction, My Personal reasons has to do with this -->"Why are conservatives so obsessed with the border and immigration?"
It's the consequence of the fear of change and diversity common to most on the right, specificity the unwarranted fear that immigrants manifest some sort of 'threat,' that America will be 'changed' in some manner detrimental to the interests of conservatives.
Much of it has to do with conservative ignorance of, or contempt for, 14th Amendment jurisprudence, where the right to due process of the law is guaranteed to all persons, including those undocumented, as one is not 'illegal' until such time as he has been found guilty of unauthorized access to the country in a court of law.
Nativism has historically been a fundamental component of conservative dogma, dating back to the late 19th Century and hostility toward immigration from Central and Eastern Europe.
Last, and unfortunately, it has to some degree to do with racism and bigotry – those who don't want to see more 'brown people' in the country. Of course this racism is not representative of all conservatives, but it does illustrate the fact that conservative dogma does attract racists, who find refuge among conservative ranks.
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