Donald Trump wants to deny the right of citizenship to some folks born here in the USA, chiefly—at least to begin with—the children of illegal immigrants from Mexico and South America. Trump doesn't stand alone in this view. With the exception of Kasich and Perry, the entire slate of GOP candidates has asserted this belief.
1.Do they care about history and fact?
2.Whom do they represent?
In answer to question #1, I highly recommend an article on this topic written by Damon Root, senior editor of Reason magazine and the author of Overruled: The Long War for Control of the U.S. Supreme Court (Palgrave Macmillan). Titled "Trump vs. the Constitution," the essay delivers a brief history of the 14th Amendment to the US Constitution, anchoring its origins with the infamous Dred Scott decision by the Supreme Court, in which Chief Justice Taney asserted that neither the Declaration of Independence nor the Constitution considered Negroes citizens, and since they had no rights then, they have no rights "which the white man is bound to respect."
Well, the 13th and 14th Amendments went a very long way toward righting some of the wrongs of the Dred Scott decision. The 13th abolished slavery, and the 14th conferred the rights of citizenship:
"All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside."
Root goes on to describe how this principal has been upheld through the centuries—applied to those of Chinese and Arabic descent, among others—and it leaves little room for the likes of Trump's views.
So, in my opinion, those advocating stripping citizenship rights from those born here of illegal parents haven't got a leg to stand on.
As to question #2, I don't know the answer. Many people on the right and left of politics have been wondering how Trump has lasted this long. I lean toward the speculation that he voices ("trumpets") anger and outrage, which as we all know, typically operate in a vacuum without the benefit of history, facts, or reason.
But I'm the same: when I feel a sense of outrage or when I feel I've been unjustly treated, I too raise my voice and rev into overdrive, without benefit of calm and reason. After all, isn't part of our birthright the freedom to speak out against the wrongs we perceive?
Thankfully, I am not a political leader, and the only ones who hear my rants are my friends and family. That's where it's different with an office holder, and I expect of political leaders the ability to resist pandering to a base emotional frustration, the integrity to deal with history honestly, and the courage to seek and embrace facts that may not support their views.