Workers leave the site of the future Trump International Hotel, Washington, D.C., at the Old Post Office Pavilion on July 6, 2015. (Matt McClain/The Washington Post)

It is not surprising that at the nominating convention of a candidate who used immigration to instill fear (They are coming to kill your kids!) and resentment (They are coming to steal your jobs!), so much absolute nonsense about immigration is spewed from the stage. But it’s not limited to the convention. Since right-wingers hit upon the idea of making legal and illegal immigrants their scapegoat, they have wallowed in misinformation, distortion and blatant lies on conservative blogs and print publications. You hear it regularly on radio talk shows and from anti-immigrant fanatics such as Sen. Jeff Sessions (R-Ala.).

It is the height of hypocrisy that Trump enthusiast Peter Thiel made his money in industries that rely on the contributions of immigrants and a functioning international economic system. I suppose he’s got his billions, so he no longer cares about preserving those industries for others. (Likewise, Tom Barrack, who spoke on Donald Trump’s behalf, is the grandson of Lebanese immigrants.)

It is hard to discern how much of the anti-immigration mishugas  stems from economic illiteracy and how much from bias and a fear that American culture will be changed by newcomers. (The idea that American culture is fixed and newcomers will bring “foreign influences” has been the basis of opposition to every wave of immigration in our history. The America of people’s childhoods, about which they wax lyrical, was already the product of waves of immigrants from around the world.)

As for the merits, there is no respectable school of economics that suggests immigration is bad for a country. (Even Trump alma mater Wharton advocates more immigration.) Businesspeople, investors and all those working in the tech world or buying its products know immigrants are a net positive. (Would we be better off if every immigrant sports figure, business founder, investor, artist and inventor went somewhere else?) Even Trump knew immigration was a plus (he surely has enough immigrants, both legal and not, at his work sites) before he thought it politically advantageous to become a know-nothing. He even excoriated Mitt Romney for being too anti-immigration in 2012. He might consult with his running mate, Indiana Gov. Mike Pence (a son of an immigrant), who was an advocate of immigration reform until it wasn’t fashionable to be.

John Cochrane, a conservative economist, explained a couple of years ago:

The most common objection is the claim that letting immigrants in will hurt American wages. Before, I’ve addressed this on its merits: If labor doesn’t move, capital will. Your doctor’s lower wages are your lower health costs. Immigrants come for wide open jobs, and to start new businesses. And so on. What occurs to me this morning is the inconsistency that conservatives make this argument. Suppose it were true. Would that mean the government should keep out migrants to keep American wages up?

Well, do you believe that the Federal government should mandate a large minimum wage, to raise American’s wages? Do you believe that the Federal Government should ban imports and subsidize exports, to raise American’s wages? Do you believe that the Federal Government should give more power to unions, to raise American’s wages? Do you believe that the Federal Government should pass even more stringent rules in its own contracts to pay higher wages? Do you believe that the government should pass more licensing restrictions, to lessen competition and raise American’s wages?

Intellectual consistency is not a strength of anti-immigrant activists.

Immigrants commit fewer crimes than native-born Americans, create more high-value businesses and file more patents. Immigrants are fueling a rebound in homeownership. Because immigrants are younger on average than native-born Americans, they are also helping to keep our entitlement programs afloat as the baby boomers retire.

For anyone who cares to get up to speed, it is easy to spot the intellectual errors that drive the insistence that immigrants are “stealing our jobs” or driving down wages. Many have pointed out that immigrants are not “pouring” over the border. The positive effects of immigration are not unique to the United States. (In Israel, for example, an influx of Russian immigrants jump-started a tech boom.) Debunked claims that immigrants depress wages nevertheless persist.

None of this is to say we don’t have legitimate concerns about assimilation and national security, but no one — sorry, Donald — no one is talking about “open borders.” Despite the overwhelming weight of evidence showing anti-immigrant activists are wrong, the anti-immigrant fanatics continue. To support their prejudice (let’s be clear, if it were all immigrants who they were concerned about, they’d be much more upset about visa overstays than the southern border), they often rely on the false data put out by anti-immigrant, zero-population-growth advocates.

BuzzFeed reported recently on the origins of phony immigration stats and the PR campaign featuring families of victims of illegal immigrants:

In 1920, speaking before a House committee on immigration, the American eugenicist Harry Laughlin explained that Italians, Russians, and Poles were disproportionately likely to end up in asylums for the criminally insane, describing them as a potential “national menace.” . . .

Laughlin, who backed up his claims of immigrant criminality with what he called “scientific” data, went on to start the Pioneer Fund, a group dedicated to studying “human nature, heredity, and eugenics.” In the 1980s, Pioneer donated $1.5 million in early financing to John Tanton’s FAIR, the group behind nearly every significant restrictionist organization in the U.S. today. Trump’s campaign announcement struck a chord that FAIR and its affiliated groups had been sounding for years.

The noxious influence of groups with roots in eugenics and zero-population-growth malarkey — about as far from modern conservatism as you can get — has been reported occasionally. Politico a few years back explained:

FAIR, NumbersUSA and CIS were started, and are staffed and funded, by a cabal of radical environmentalists, zero population ideologues and Planned Parenthood promoters. They are wedded to the long-discredited Malthusian view that “people are pollution” and believe that the only way to control poverty and other social ills is to limit, and if possible, reduce the population of the planet.

Here is the conclusion of a recently published in-depth study in Human Life Review: “The evidence shows that the primary leaders and funders of the anti-immigration movement were drawn to it because they were also active organizers and supporters of, and contributors to, the population-control movement in the United States.” They are no more passionate about cutting off immigration than they are about curbing our domestic population by means of unlimited abortion rights. . . .

All three groups are the creation of John Tanton, who is (in the words of the Human Life Review article) “the father of the population-control wing of the modern anti-immigration movement” and who has had senior leadership positions in Planned Parenthood, Zero Population Growth and the Sierra Club. As Tanton himself notes, he was “drawn to Planned Parenthood by an imbalance between human numbers and available resources.”

Given how gullible Trump is about conspiracy theories and urban myths, the anti-immigrant network has found its perfect mark. (For many years, these fanatics had an eager consumer in top Trump adviser Sessions, who uncritically repeats their work although his poor state could use some immigrants.) It behooves honest conservatives and the media to pull back the curtain on the creepy anti-immigrant movement, call out its misinformation and stop laundering its fake data.

There are honest debates to be had about immigration, both legal and illegal. Preventing visa overstays and promoting assimilation are real issues.We might get to those topics, but only if we dispense with blatantly dishonest arguments from Malthusians misrepresented as fact.