Trump is obviously an idiot, but his hostility to immigration shows how clueless he and his fan-base really are.
(1) From a national perspective, welcoming immigrants has been a mark of enlightened thinking. The U.S. was founded by immigrants and has prided itself on being open to diversity. For all its troubled history with Native American ethnic cleansing and African American slavery, the nation was built on principles which advocate equal opportunity for all. When a president like Benjamin Harrison called for needless restrictions on Asian immigrants, he was judged for it accordingly. Americans have historically resisted the equation of nationality with ethnicity. Nationality has been about citizenship, and allegiance to the vision of the founding fathers.
(2) From an economic perspective, immigration has always been the life’s blood of the U.S., infusing new ideas and skills into the American market. Immigration has given the country new jobs, new businesses, new inventions. Immigrants create new populations of people who buy things. People tend to fear job competition in times of hardship or depression — and the threat of having jobs “stolen” from them — but the fact is that a bigger workforce means more consumption, more demand, and more jobs. That’s the long-standing wisdom of economists. Thwarting immigration is a likely path to slowing economic growth.
(3) From a Judeo-Christian religious perspective, one could make a strong case to be pro-immigration. According to even a hard-core fundamentalist like Pastor Steven Anderson, God specifically tells his followers to welcome and love the immigrant: “The stranger (immigrant) that dwells with you shall be as one born among you, and you shall love him as yourself.” (Leviticus 19:34). “You shall neither vex a stranger nor oppress him, for you were strangers in the land of Egypt.” (Exodus 22:21; cf.23:9; Leviticus 19:33). After all, says Anderson, everyone in America descends from immigrants (aside from the Native American Indians), and those who have a problem with immigrants “should probably leave the country themselves”. There is also the example of Ruth, who wondered why she should receive grace, given that she was an immigrant from Moab. Yet Boaz took care of her anyway, and told others to treat her well. (Ruth 2:10-16)
In light of the support Trump receives from “patriotic” nationalists, entrepreneurs, and conservative Christians, the irony is amusing.