It would take about 15 years before the United States experienced a net decline in immigration under an amnesty proposal offered by President Donald Trump, according to an analysis released Wednesday by a think tank that favors less immigration.

The plan, which Trump reiterated during Tuesday’s State of the Union address, would grant amnesty to 1.8 million young adult illegal immigrants and reduce certain categories of immigration.

The study by the Washington-based Center for Immigration Studies (CIS) concludes that Trump’s proposal would result in an immediate 18 percent cut in legal migration and a 33 percent reduction after 10 years.

But the 10-year total reduction would be less than the 1.8 million new lawful permanent residents that would be added after the so-called dreamers — whose parents brought them as young children to America — gained green cards. The term derives from the Development, Relief, and Education for Alien Minors (DREAM) Act.

The report’s author, Jessica Vaughan, said that after about 15 years, overall immigration would tumble fairly significantly. The plan as envisioned by the White House represents an improvement over the current system, which awards more than 1 million new green cards every single year, she said. But she added that the final bill emerging from Congress likely would restore some of the legal immigration cuts the president proposes.

[lz_ndn video=33489281]

“I think this proposal would be better than the status quo … But I don’t think that would be the end of it,” said Vaughan, director of policy studies at the think tank.

The United States gave out 1.16 million green cards in fiscal year 2016. Under Trump’s plan, that would drop to 963,000, according to the study. Most that drop would be the result of the elimination of the diversity visa lottery — which awards about 50,000 green cards to applicants chosen randomly from around the world — and changes to chain migration, the sponsoring by U.S. residents of new immigrants based solely on family relation.

[lz_table title=”Trump’s Immigration Plan” source=”Center for Immigration Studies”]Impact on green cards
|Category,Year 5,Year 10
Family,-169K,-332K
Employment,+25K*,No change
Lottery,-50K,-$50K
Humanitarian,-6K,-6K
Amnesty,1.8M,No change
|Total change,1.6M,-388K
*Includes reallocation of diversity lottery green cards
[/lz_table]

Currently, immigrants can sponsor their children up to the age of 21. Under the proposal, 18 would be the cutoff age. Citing Department of Homeland Security data, the report notes that about 52,000 young adults aged 18 through 20 come to the United States every year under the child category.

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The number of green cards would bulge dramatically in five years — to an estimated 2.7 million — as dreamers received amnesty. Vaughan said it would take years for the full effects of changes to chain migration to kick in because they would not apply to some 3.9 million people currently on waiting lists to immigrate under various categories that cap the number of annual admissions.

By year 10, however, the number of admissions would be about 775,000, and the numbers would fall rapidly over the next decade.

Vaughan said overall migration to the United States might decline even further if Congress were to adopt other measures proposed by Trump, including a $25 billion trust fund to build a wall and implement additional security measures, along with closing legal loopholes that slow deportations.

“Especially if you consider that this is a package, you would have fewer illegal immigrants,” she said.

But Vaughan pointed to another factor that could mitigate the reduction in lawful permanent residents — a provision in leading Senate proposals that would create a new nonimmigrant visa for citizens’ parents, who no longer would be eligible for green cards.

Although those parents would not be allowed to work in the United States, their overall numbers could be similar to parents currently admitted on green cards, she said.

Trump’s plan has drawn fire from traditional allies in the immigration debate. David Cross, a spokesman for Oregonians for Immigration Reform, said he does not believe “trivial” changes in chain migration are worth giving amnesty to nearly 2 million people.

“Not for such low numbers (of reductions) over a long period of time,” he said. “Congresses can change. Presidents can change.”

Cross said he worries a large amnesty would provoke a new rush for the U.S. border.

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“I think it stepped away from the president’s campaign promise,” he said. “This is not what he ran to do.”

Vaughan said the details of actual legislation matter greatly.

“I could live with this and even support it if that were the end of the negotiations,” she said.

But Vaughan added that she fears legislation that emerges from negotiations would move a lot further in the direction of lawmakers who want a “clean” amnesty for dreamers, with fewer restrictions on legal immigration.

PoliZette senior writer Brendan Kirby can be reached at [email protected]. Follow him on Twitter.

(photo credit, homepage image: Dreamer Protest, CC BY 2.0, by Molly Adams; photo credit, article image: Dreamer Protest, CC BY 2.0, by Molly Adams)