Trump's border wall

Illegal immigration was a signature issue of President Donald Trump's presidential campaign, and his proposed reforms and remarks about this issue have generated headlines. A hallmark promise of his campaign was to build a substantial wall on the United States-Mexico border. Trump has also expressed support for a variety of "limits on legal immigration and guest-worker visas", including a "pause" on granting green cards, which Trump says will "allow record immigration levels to subside to more moderate historical averages". Trump's proposals regarding H-1B visas have frequently changed throughout his presidential campaign, but as of late July 2016, he appears to oppose the H-1B visa program. Trump has questioned official estimates of the number of illegal immigrants in the United States (between 11 and 12 million), insisting the number is much higher (between 30 and 34 million).

Trump has questioned official estimates of the number of illegal immigrants in the United States (between 11 and 12 million), asserting that the number is actually between 30 and 34 million. PolitiFact ruled that his statement was "Pants on Fire", citing experts who noted that no evidence supported an estimate in that range. For example, the Pew Research Center reported in March 2015 that the number of illegal immigrants overall declined from 12.2 million in 2007 to 11.2 million in 2012. The number of illegal immigrants in the U.S. labor force ranged from 8.1 million to 8.3 million between 2007 and 2012, approximately 5% of the U.S. labor force.

Trump proposes rolling back birthright citizenship - a historically broadened interpretation of the Citizenship Clause of the Fourteenth Amendment that all persons born on U.S. soil are citizens - so as not to grant citizenship to US-born children of illegal immigrants (whom he refers to as "anchor babies"). The mainstream view of the Fourteenth Amendment among legal experts is that everyone born on U.S. soil, regardless of parents' citizenship, is automatically an American citizen.

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