Here are some portions of the LARGE and EXCELLENT article at THE ATLANTIC JOURNAL:
…In 2005, a left-leaning blogger wrote, “Illegal immigration wreaks havoc economically, socially, and culturally; makes a mockery of the rule of law; and is disgraceful just on basic fairness grounds alone.” In 2006, a liberal columnist wrote that “immigration reduces the wages of domestic workers who compete with immigrants” and that “the fiscal burden of low-wage immigrants is also pretty clear.” His conclusion: “We’ll need to reduce the inflow of low-skill immigrants.” That same year, a Democratic senator wrote, “When I see Mexican flags waved at proimmigration demonstrations, I sometimes feel a flush of patriotic resentment. When I’m forced to use a translator to communicate with the guy fixing my car, I feel a certain frustration.”
The blogger was Glenn Greenwald. The columnist was Paul Krugman. The senator was Barack Obama.
Prominent liberals didn’t oppose immigration a decade ago. Most acknowledged its benefits to America’s economy and culture. They supported a path to citizenship for the undocumented. Still, they routinely asserted that low-skilled immigrants depressed the wages of low-skilled American workers and strained America’s welfare state. And they were far more likely than liberals today are to acknowledge that, as Krugman put it, “immigration is an intensely painful topic … because it places basic principles in conflict.”
Today, little of that ambivalence remains. In 2008, the Democratic platform called undocumented immigrants “our neighbors.” But it also warned, “We cannot continue to allow people to enter the United States undetected, undocumented, and unchecked,” adding that “those who enter our country’s borders illegally, and those who employ them, disrespect the rule of the law.” By 2016, such language was gone. The party’s platform described America’s immigration system as a problem, but not illegal immigration itself. And it focused almost entirely on the forms of immigration enforcement that Democrats opposed. In its immigration section, the 2008 platform referred three times to people entering the country “illegally.” The immigration section of the 2016 platform didn’t use the word illegal, or any variation of it, at all.
“A decade or two ago,” says Jason Furman, a former chairman of President Obama’s Council of Economic Advisers, “Democrats were divided on immigration. Now everyone agrees and is passionate and thinks very little about any potential downsides.” How did this come to be?
[….]
A larger explanation is political. Between 2008 and 2016, Democrats became more and more confident that the country’s growing Latino population gave the party an electoral edge. To win the presidency, Democrats convinced themselves, they didn’t need to reassure white people skeptical of immigration so long as they turned out their Latino base. “The fastest-growing sector of the American electorate stampeded toward the Democrats this November,” Salon declared after Obama’s 2008 win. “If that pattern continues, the GOP is doomed to 40 years of wandering in a desert.”
[….]
Alongside pressure from pro-immigrant activists came pressure from corporate America, especially the Democrat-aligned tech industry, which uses the H-1B visa program to import workers. In 2010, New York Mayor Michael Bloomberg, along with the CEOs of companies including Hewlett-Packard, Boeing, Disney, and News Corporation, formed New American Economy to advocate for business-friendly immigration policies. Three years later, Mark Zuckerberg and Bill Gates helped found FWD.us to promote a similar agenda.
This combination of Latino and corporate activism made it perilous for Democrats to discuss immigration’s costs, as Bernie Sanders learned the hard way. In July 2015, two months after officially announcing his candidacy for president, Sanders was interviewed by Ezra Klein, the editor in chief of Vox. Klein asked whether, in order to fight global poverty, the U.S. should consider “sharply raising the level of immigration we permit, even up to a level of open borders.” Sanders reacted with horror. “That’s a Koch brothers proposal,” he scoffed. He went on to insist that “right-wing people in this country would love … an open-border policy. Bring in all kinds of people, work for $2 or $3 an hour, that would be great for them. I don’t believe in that. I think we have to raise wages in this country.”
Sanders came under immediate attack. Vox’s Dylan Matthews declared that his “fear of immigrant labor is ugly—and wrongheaded.” The president of FWD.us accused Sanders of “the sort of backward-looking thinking that progressives have rightly moved away from in the past years.” ThinkProgress published a blog post titled “Why Immigration Is the Hole in Bernie Sanders’ Progressive Agenda.” The senator, it argued, was supporting “the idea that immigrants coming to the U.S. are taking jobs and hurting the economy, a theory that has been proven incorrect.”
Sanders stopped emphasizing immigration’s costs. By January 2016, FWD.us’s policy director noted with satisfaction that he had “evolved on this issue.”
But has the claim that “immigrants coming to the U.S. are taking jobs” actually been proved “incorrect”? A decade ago, liberals weren’t so sure. In 2006, Krugman wrote that America was experiencing “large increases in the number of low-skill workers relative to other inputs into production, so it’s inevitable that this means a fall in wages.”
It’s hard to imagine a prominent liberal columnist writing that sentence today. To the contrary, progressive commentators now routinely claim that there’s a near-consensus among economists on immigration’s benefits.