WASHINGTON — President Trump embraced a proposal Wednesday to slash legal immigration to the United States in half within a decade by sharply curtailing the ability of US citizens and legal residents to bring family members into the country.
The plan would enact the most far-reaching changes to the system of legal immigration in decades and represents the president’s latest effort to stem the flow of newcomers to the United States. Since taking office, he has barred many visitors from select Muslim-majority countries, limited the influx of refugees, increased deportations, and pressed to build a wall along the southern border.
In asking Congress to curb legal immigration, Trump intensified a debate about national identity, economic growth, worker fairness, and American values that animated his campaign last year. Critics said the proposal would undercut the fundamental vision of the United States as a haven for the poor and huddled masses, while the president and his allies said the country had taken in too many low-skilled immigrants for too long to the detriment of American workers.
“This legislation will not only restore our competitive edge in the 21st century, but it will restore the sacred bonds of trust between America and its citizens,” Trump said at a White House event alongside two Republican senators sponsoring the bill. “This legislation demonstrates our compassion for struggling American families who deserve an immigration system that puts their needs first and that puts America first.”
In throwing his weight behind a bill, Trump added one more long-odds priority to a legislative agenda already struggling, in the wake of the defeat of legislation to repeal and replace former president Barack Obama’s health care program. The president has vowed to overhaul the tax code and rebuild the nation’s roads, airports, and other infrastructure.
But by endorsing legal immigration cuts, a move he has long supported, Trump returned to a theme that has defined his short political career and excites his conservative base at a time when his poll numbers continue to sink.
Democrats and some Republicans quickly criticized the move. “Instead of catching criminals, Trump wants to tear apart communities and punish immigrant families that are making valuable contributions to our economy,” said Tom Perez, the chairman of the Democratic National Committee. “That’s not what America stands for.”
The bill, sponsored by Senators Tom Cotton, Republican of Arkansas, and David Perdue, Republican of Georgia, would institute a merit-based system to determine who is admitted to the country and granted legal residency green cards, favoring applicants based on skills, education, and language ability rather than relations with people already here. The proposal revives an idea included in broader immigration legislation supported by President George W. Bush that died in 2007.
More than 1 million people are granted legal residency each year, and the proposal would reduce that by 41 percent in its first year and 50 percent by its 10th year, according to projections cited by its sponsors. The reductions would come largely from those brought in through family connections. The number of immigrants granted legal residency on the basis of job skills, about 140,000, would remain roughly the same.
Under the current system, most legal immigrants are admitted to the United States based on family ties. US citizens can sponsor spouses, parents, and minor children for an unrestricted number of visas, while siblings and adult children are given preferences for a limited number of visas available to them.
Legal permanent residents holding green cards can also sponsor spouses and children.
In 2014, 64 percent of immigrants admitted with legal residency were immediate relatives of US citizens or sponsored by family members. Just 15 percent entered through employment-based preferences, according to the Migration Policy Institute, an independent research organization.
But that does not mean that those who came in on family ties were necessarily low skilled or uneducated.
The legislation would award points based on education, ability to speak English, high-paying job offers, age, record of achievement, and entrepreneurial initiative. But while it would still allow spouses and minor children of Americans and legal residents to come in, it would eliminate preferences for other relatives, like siblings and adult children. The bill would create a renewable temporary visa for older-adult parents who come for caretaking purposes.
The legislation would limit refugees offered permanent residency to 50,000 a year and eliminate a diversity visa lottery that the sponsors said does not promote diversity.
The projections cited by the sponsors said legal immigration would decrease to 637,960 after a year and to 539,958 after a decade.
Cotton said low-skilled immigrants push down wages for those who worked with their hands. “For some people, they may think that that’s a symbol of America’s virtue and generosity,” he said. “I think it’s a symbol that we’re not committed to working-class Americans and we need to change that.”
But Senator Lindsey Graham, Republican of South Carolina, noted that agriculture and tourism were his state’s top two industries. “If this proposal were to become law, it would be devastating to our state’s economy, which relies on this immigrant workforce,” he said.
The National Immigration Forum, an advocacy group, said the country was already facing a workforce gap of 7.5 million jobs by 2020.
The plan endorsed by Trump generated a fiery exchange at the White House briefing when Stephen Miller, the president’s policy adviser, defended the proposal. Pressed for statistics to back up claims that immigration was costing Americans jobs, he cited several studies that have been debated by experts.
“But let’s also use common sense here, folks,” Miller said. “At the end of the day, why do special interests want to bring in more low-skill workers?”
When a reporter read him some of the words from the Statue of Liberty — “Give me your tired, your poor, your huddled masses yearning to breathe free” — Miller dismissed them. “The poem that you’re referring to was added later,” he said. “It’s not actually part of the original Statue of Liberty.”
US Senator Edward J. Markey, a Massachusetts Democrat, condemned Trump’s push to reduce legal immigration.
Instead of focusing on xenophobic half measures, the Trump administration should support comprehensive immigration reform and help create a pathway to citizenship for the millions of immigrants who are our family members, neighbors, co-workers, and friends,” Markey said.
US Senator Elizabeth Warren of Massachusetts said the Trump approach “makes no sense.’’
“We need comprehensive immigration reform, not shortsighted policies that pick on refugees and legal immigrants — and don’t fix any of the actual problems with our immigration system,” she said.
Governor Charlie Baker’s spokeswoman released a statement that praised the value of immigration but did not directly address whether Baker supports or opposes the bill. Baker called on Washington to “fix the broken immigration system and secure our borders with comprehensive, bipartisan legislation.’’
Michael Levenson and Andy Rosen of the Globe staff contributed to this report.