Although this topic is closely related to the discussions about the shutdown, it needs to be examined separately because it is a VERY complicated issue.
Trump has long used immigration as a "wedge" issue to separate his base from the more rational members of society, which is why he first started claiming, in 2010, that Obama was born in Kenya - and he was far from the only politician that was saying the same thing:
From the opening salvo of his presidential campaign, he started picking on immigrants. He claimed that Mexicans were "drug dealers, criminals, and rapists". He claimed that the only way to stop them was to build a "big, beautiful wall" - and Mexico was going to pay for it.
Since Mexico clearly was never going to pay for it, he is now using the extortion of a government shutdown to force the TAXPAYERS to pay for it, since he claims that the cost of illegal immigrants is FAR greater than the cost of his stupid wall. The other day, he actually said that the cost of illegal immigration was "over $200 billion" a year".
Where in the world did he come up with THAT number?
Lord knows, but a large part of the blame can be attributed to the Heritage Foundation, the conservative think tank that was started in 1973. Here are two key paragraphs from the Wikipedia article about the organization:
The Heritage Foundation has been described as a major influence on the presidential transition of Donald Trump and the Trump administration. The foundation had a powerful say in the staffing of the administration, with CNN noting during the transition that "no other Washington institution has that kind of footprint in the transition." One reason for the Heritage Foundation's disproportionate influence relative to other conservative think tanks is that other conservative think tanks had members who identified as "never-Trumpers" during the 2016 election, whereas the Heritage Foundation signaled early on to Trump that it would be supportive of him.
In 2014, the Heritage Foundation began building a database of approximately 3,000 conservatives who they trusted to serve in a hypothetical Republican administration for the upcoming 2016 election. According to individuals involved in crafting the database, several hundred people from the Heritage database ultimately received jobs in the Trump administration At least 66 foundation employees and alumni got positions in the administration. The foundation also recommended cabinet members Scott Pruitt, Betsy DeVos, Mick Mulvaney, Rick Perry, and Jeff Sessions. Heritage head Jim DeMint personally intervened on behalf of Mulvaney, who would go on to head the Office of Management and Budget and the Consumer Financial Protection Bureau. On December 14, Mulvaney also became the acting chief of staff - largely because no one else wanted the job.
The Heritage Foundation is very much anti-immigrant. If you really have a LOT of patience, you can read their 30 page analysis of the cost of illegal immigrants - but I would not recommend it.
If you really wanted to get an ACCURATE picture of the cost/benefits of illegal immigrants, the best source is the non-partisan Congressional Budget Office. Their analysis is much shorter, at 12 pages, but it takes 4 more to list the bibiolgraphy of source material:
The short version of their analysis, though, is this:
"Over the past two decades, most efforts to estimate the fiscal impact of immigration in the United States have concluded that, in aggregate and over the long term, tax revenues of all types generated by immigrants—both legal and unauthorized—exceed the cost of the services they use."
One organization that was inspired by the Heritage Foundation was the Federation for American Immigration Reform (FAIR), which was founded in 1979. It has managed to come up with some truly wacky numbers about immigration. According to the Southern Poverty Law Center, though, FAIR (which has ties to white supremacist groups and eugenicists) is far from a reliable source. In spite of that, some of the former employees of FAIR have now found jobs in the Trump administration.
One of the reports that FAIR developed was that illegal immigration was costing us $338.3 billion a year. Fortunately, the folks at FactCheck.org were able to point out how dumb that number was:
The numbers produced by FAIR have been used by a wide variety of politicians. In June of 2018, Paul Gosar, a member of the House Freedom Caucus, claimed that illegal immigration costs us over $100 billion a year. The fact checkers at the Arizona Republic gave him One Star: Mostly false. If you read the article below in its entirety, you'll notice that the source material that was used is VERY extensive.
In 2016, Trump stated that illegal immigrants cost us $113 billion a year. By January of 2018, that number had soared to $296 billion. An analysis by Politifact concluded that that number was way off, and that "the overall effect of immigration on economic growth was positive."
An organization called Illuminate our world debunked 10 immigration myths in August of 2018:
In July of 2012, the Obama White House published a list of 10 ways that immigrants help build and strengthen our economy:
The folks who are regular viewers of the FOX network aren't going to believe any of the information that I listed above. They are going to continue to believe the nonsense spouted by Trump's "deputy chief of staff", Sean Hannity, and nothing any of us say will change their mind. The town hall meeting of August 8, 2016, with Trump, Hannity, and Sebastian Gorka gave us a hint of what we might expect going forward:
(You may remember that Gorka became deputy assistant to Trump in January of 2017, but he was never able to obtain the security clearance necessary for national security issues, and he "resigned" in August of 2017, one week after Bannon left.)